Describe changes to Carp and Carp::Heavy
[p5sagit/p5-mst-13.2.git] / INSTALL
CommitLineData
f1300be0 1If you read this file _as_is_, just ignore the funny characters you see.
2It is written in the POD format (see pod/perlpod.pod) which is specially
3designed to be readable as is.
4
8e07c86e 5=head1 NAME
6
7df75831 7Install - Build and Installation guide for perl 5.
8e07c86e 8
9=head1 SYNOPSIS
10
7df75831 11First, make sure you have an up-to-date version of Perl. If you
ce80d64e 12didn't get your Perl source from CPAN, check the latest version at
13http://www.cpan.org/src/. Perl uses a version scheme where even-numbered
08854360 14subreleases (like 5.8.x and 5.10.x) are stable maintenance releases and
ce80d64e 15odd-numbered subreleases (like 5.7.x and 5.9.x) are unstable
16development releases. Development releases should not be used in
17production environments. Fixes and new features are first carefully
18tested in development releases and only if they prove themselves to be
19worthy will they be migrated to the maintenance releases.
3ce0d271 20
7df75831 21The basic steps to build and install perl 5 on a Unix system with all
dd3196cd 22the defaults are to run, from a freshly unpacked source tree:
8e07c86e 23
491517e0 24 sh Configure -de
8e07c86e 25 make
26 make test
27 make install
36477c24 28
8e07c86e 29Each of these is explained in further detail below.
30
cc65bb49 31The above commands will install Perl to /usr/local (or some other
32platform-specific directory -- see the appropriate file in hints/.)
7df75831 33If that's not okay with you, you can run Configure interactively, by
ff52061e 34just typing "sh Configure" (without the -de args). You can also specify
35any prefix location by adding "-Dprefix='/some/dir'" to Configure's args.
36To explicitly name the perl binary, use the command
37"make install PERLNAME=myperl".
491517e0 38
ff52061e 39These options, and many more, are explained in further detail below.
7f678428 40
8d74ce1c 41If you have problems, corrections, or questions, please see
ff52061e 42L<"Reporting Problems"> below.
8d74ce1c 43
7beaa944 44For information on what's new in this release, see the
9519d2ec 45pod/perl5110delta.pod file. For more information about how to find more
46specific detail about changes, see the Changes file.
c3edaffb 47
1ec51d55 48=head1 DESCRIPTION
edb1cbcb 49
c3edaffb 50This document is written in pod format as an easy way to indicate its
51structure. The pod format is described in pod/perlpod.pod, but you can
1ec51d55 52read it as is with any pager or editor. Headings and items are marked
53by lines beginning with '='. The other mark-up used is
54
55 B<text> embolden text, used for switches, programs or commands
56 C<code> literal code
57 L<name> A link (cross reference) to name
ce80d64e 58 F<file> A filename
1ec51d55 59
c42e3e15 60Although most of the defaults are probably fine for most users,
ce80d64e 61you should probably at least skim through this document before
1ec51d55 62proceeding.
c3edaffb 63
ce80d64e 64In addition to this file, check if there is a README file specific to
65your operating system, since it may provide additional or different
66instructions for building Perl. If there is a hint file for your
dd3196cd 67system (in the hints/ directory) you might also want to read it
68for even more information.
c42e3e15 69
ce80d64e 70For additional information about porting Perl, see the section on
71L<"Porting information"> below, and look at the files in the Porting/
72directory.
d56c5707 73
ce80d64e 74=head1 PRELIMINARIES
c42e3e15 75
ce80d64e 76=head2 Changes and Incompatibilities
c42e3e15 77
4eeeaff6 78Please see pod/perl5110delta.pod for a description of the changes and
ce80d64e 79potential incompatibilities introduced with this release. A few of
80the most important issues are listed below, but you should refer
4eeeaff6 81to pod/perl5110delta.pod for more detailed information.
c42e3e15 82
fdd3cf50 83B<WARNING:> This version is not binary compatible with prior releases of Perl.
cc65bb49 84If you have built extensions (i.e. modules that include C code)
64fa5b0b 85using an earlier version of Perl, you will need to rebuild and reinstall
86those extensions.
1b1c1ae2 87
88Pure perl modules without XS or C code should continue to work fine
dd3196cd 89without reinstallation. See the discussion below on
7df75831 90L<"Coexistence with earlier versions of perl 5"> for more details.
693762b4 91
92The standard extensions supplied with Perl will be handled automatically.
93
ce80d64e 94On a related issue, old modules may possibly be affected by the changes
95in the Perl language in the current release. Please see
4eeeaff6 96pod/perl5110delta.pod for a description of what's changed. See your
ce80d64e 97installed copy of the perllocal.pod file for a (possibly incomplete)
98list of locally installed modules. Also see CPAN::autobundle for one
99way to make a "bundle" of your currently installed modules.
16dc217a 100
aa689395 101=head1 Run Configure
8e07c86e 102
103Configure will figure out various things about your system. Some
104things Configure will figure out for itself, other things it will ask
d6baa268 105you about. To accept the default, just press RETURN. The default is
106almost always okay. It is normal for some things to be "NOT found",
107since Configure often searches for many different ways of performing
108the same function.
109
ce80d64e 110At any Configure prompt, you can type &-d and Configure will use the
d6baa268 111defaults from then on.
8e07c86e 112
113After it runs, Configure will perform variable substitution on all the
1ec51d55 114*.SH files and offer to run make depend.
8e07c86e 115
dd3196cd 116The results of a Configure run are stored in the config.sh and Policy.sh
117files.
118
ce80d64e 119=head2 Common Configure options
844fc9f4 120
ce80d64e 121Configure supports a number of useful options. Run
844fc9f4 122
ce80d64e 123 Configure -h
d6baa268 124
ce80d64e 125to get a listing. See the Porting/Glossary file for a complete list of
fb73857a 126Configure variables you can set and their definitions.
127
d6baa268 128=over 4
129
08854360 130=item C compiler
d6baa268 131
08854360 132To compile with gcc, if it's not the default compiler on your
133system, you should run
8e07c86e 134
135 sh Configure -Dcc=gcc
136
08854360 137This is the preferred way to specify gcc (or any another alternative
8e07c86e 138compiler) so that the hints files can set appropriate defaults.
139
d6baa268 140=item Installation prefix
4633a7c4 141
8e07c86e 142By default, for most systems, perl will be installed in
8d74ce1c 143/usr/local/{bin, lib, man}. (See L<"Installation Directories">
7df75831 144and L<"Coexistence with earlier versions of perl 5"> below for
8d74ce1c 145further details.)
146
147You can specify a different 'prefix' for the default installation
ce80d64e 148directory when Configure prompts you, or by using the Configure command
8d74ce1c 149line option -Dprefix='/some/directory', e.g.
8e07c86e 150
25f94b33 151 sh Configure -Dprefix=/opt/perl
4633a7c4 152
d6baa268 153If your prefix contains the string "perl", then the suggested
154directory structure is simplified. For example, if you use
155prefix=/opt/perl, then Configure will suggest /opt/perl/lib instead of
156/opt/perl/lib/perl5/. Again, see L<"Installation Directories"> below
bc70e9ec 157for more details. Do not include a trailing slash, (i.e. /opt/perl/)
158or you may experience odd test failures.
8e07c86e 159
8d74ce1c 160NOTE: You must not specify an installation directory that is the same
161as or below your perl source directory. If you do, installperl will
162attempt infinite recursion.
84902520 163
d6baa268 164=item /usr/bin/perl
165
166It may seem obvious, but Perl is useful only when users can easily
167find it. It's often a good idea to have both /usr/bin/perl and
dd64f1c3 168/usr/local/bin/perl be symlinks to the actual binary. Be especially
d6baa268 169careful, however, not to overwrite a version of perl supplied by your
b66c6cec 170vendor unless you are sure you know what you are doing. If you insist
171on replacing your vendor's perl, useful information on how it was
172configured may be found with
173
174 perl -V:config_args
175
176(Check the output carefully, however, since this doesn't preserve
ce80d64e 177spaces in arguments to Configure. For that, you have to look carefully
178at config_arg1, config_arg2, etc.)
d6baa268 179
ce80d64e 180By default, Configure will not try to link /usr/bin/perl to the current
181version of perl. You can turn on that behavior by running
d6baa268 182
7d56c962 183 Configure -Dinstallusrbinperl
d6baa268 184
7d56c962 185or by answering 'yes' to the appropriate Configure prompt.
d6baa268 186
ce80d64e 187In any case, system administrators are strongly encouraged to put
188(symlinks to) perl and its accompanying utilities, such as perldoc,
4682965a 189into a directory typically found along a user's PATH, or in another
190obvious and convenient place.
191
71c4561b 192=item Building a development release
04d420f9 193
ce80d64e 194For development releases (odd subreleases, like 5.9.x) if you want to
195use Configure -d, you will also need to supply -Dusedevel to Configure,
196because the default answer to the question "do you really want to
197Configure a development version?" is "no". The -Dusedevel skips that
198sanity check.
d6baa268 199
200=back
8e07c86e 201
203c3eec 202If you are willing to accept all the defaults, and you want terse
203output, you can run
204
205 sh Configure -des
206
dd3196cd 207=head2 Altering Configure variables for C compiler switches etc.
46bb10fb 208
ce80d64e 209For most users, most of the Configure defaults are fine, or can easily
210be set on the Configure command line. However, if Configure doesn't
211have an option to do what you want, you can change Configure variables
212after the platform hints have been run by using Configure's -A switch.
213For example, here's how to add a couple of extra flags to C compiler
214invocations:
46bb10fb 215
08854360 216 sh Configure -Accflags="-DPERL_EXTERNAL_GLOB -DNO_HASH_SEED"
46bb10fb 217
5247441a 218To clarify, those ccflags values are not Configure options; if passed to
dd3196cd 219Configure directly, they won't do anything useful (they will define a
220variable in config.sh, but without taking any action based upon it).
221But when passed to the compiler, those flags will activate #ifdefd code.
5247441a 222
ce80d64e 223For more help on Configure switches, run
46bb10fb 224
ce80d64e 225 sh Configure -h
46bb10fb 226
ce80d64e 227=head2 Major Configure-time Build Options
46bb10fb 228
ce80d64e 229There are several different ways to Configure and build perl for your
230system. For most users, the defaults are sensible and will work.
231Some users, however, may wish to further customize perl. Here are
232some of the main things you can change.
46bb10fb 233
ce80d64e 234=head3 Threads
cc65bb49 235
ce80d64e 236On some platforms, perl can be compiled with support for threads. To
237enable this, run
4633a7c4 238
ce80d64e 239 sh Configure -Dusethreads
4633a7c4 240
ce80d64e 241The default is to compile without thread support.
cc65bb49 242
47f9f84c 243Perl used to have two different internal threads implementations. The current
244model (available internally since 5.6, and as a user-level module since 5.8) is
245called interpreter-based implementation (ithreads), with one interpreter per
246thread, and explicit sharing of data. The (deprecated) 5.005 version
247(5005threads) has been removed for release 5.10.
d6baa268 248
ce80d64e 249The 'threads' module is for use with the ithreads implementation. The
47f9f84c 250'Thread' module emulates the old 5005threads interface on top of the current
251ithreads model.
d6baa268 252
ce80d64e 253When using threads, perl uses a dynamically-sized buffer for some of
254the thread-safe library calls, such as those in the getpw*() family.
255This buffer starts small, but it will keep growing until the result
256fits. To get a fixed upper limit, you should compile Perl with
257PERL_REENTRANT_MAXSIZE defined to be the number of bytes you want. One
258way to do this is to run Configure with
08854360 259C<-Accflags=-DPERL_REENTRANT_MAXSIZE=65536>.
d6baa268 260
08854360 261=head3 Large file support
b367e8b0 262
ce80d64e 263Since Perl 5.6.0, Perl has supported large files (files larger than
2642 gigabytes), and in many common platforms like Linux or Solaris this
265support is on by default.
d6baa268 266
ce80d64e 267This is both good and bad. It is good in that you can use large files,
268seek(), stat(), and -s them. It is bad in that if you are interfacing Perl
269using some extension, the components you are connecting to must also
270be large file aware: if Perl thinks files can be large but the other
271parts of the software puzzle do not understand the concept, bad things
08854360 272will happen.
d6baa268 273
ce80d64e 274There's also one known limitation with the current large files
275implementation: unless you also have 64-bit integers (see the next
276section), you cannot use the printf/sprintf non-decimal integer formats
277like C<%x> to print filesizes. You can use C<%d>, though.
d6baa268 278
71c4561b 279If you want to compile perl without large file support, use
280
281 sh Configure -Uuselargefiles
282
08854360 283=head3 64 bit support
d6baa268 284
08854360 285If your platform does not run natively at 64 bits, but can simulate
286them with compiler flags and/or C<long long> or C<int64_t>,
ce80d64e 287you can build a perl that uses 64 bits.
d6baa268 288
ce80d64e 289There are actually two modes of 64-bitness: the first one is achieved
290using Configure -Duse64bitint and the second one using Configure
291-Duse64bitall. The difference is that the first one is minimal and
292the second one maximal. The first works in more places than the second.
d6baa268 293
ce80d64e 294The C<use64bitint> option does only as much as is required to get
29564-bit integers into Perl (this may mean, for example, using "long
296longs") while your memory may still be limited to 2 gigabytes (because
297your pointers could still be 32-bit). Note that the name C<64bitint>
298does not imply that your C compiler will be using 64-bit C<int>s (it
299might, but it doesn't have to). The C<use64bitint> simply means that
300you will be able to have 64 bit-wide scalar values.
d6baa268 301
ce80d64e 302The C<use64bitall> option goes all the way by attempting to switch
303integers (if it can), longs (and pointers) to being 64-bit. This may
304create an even more binary incompatible Perl than -Duse64bitint: the
305resulting executable may not run at all in a 32-bit box, or you may
306have to reboot/reconfigure/rebuild your operating system to be 64-bit
307aware.
d6baa268 308
08854360 309Natively 64-bit systems need neither -Duse64bitint nor -Duse64bitall.
0e78eb44 310On these systems, it might be the default compilation mode, and there
311is currently no guarantee that passing no use64bitall option to the
312Configure process will build a 32bit perl. Implementing -Duse32bit*
313options is planned for perl 5.12.
d6baa268 314
ce80d64e 315=head3 Long doubles
d6baa268 316
ce80d64e 317In some systems you may be able to use long doubles to enhance the
318range and precision of your double precision floating point numbers
319(that is, Perl's numbers). Use Configure -Duselongdouble to enable
320this support (if it is available).
d6baa268 321
ce80d64e 322=head3 "more bits"
b367e8b0 323
ce80d64e 324You can "Configure -Dusemorebits" to turn on both the 64-bit support
325and the long double support.
b367e8b0 326
ce80d64e 327=head3 Algorithmic Complexity Attacks on Hashes
504f80c1 328
329In Perls 5.8.0 and earlier it was easy to create degenerate hashes.
330Processing such hashes would consume large amounts of CPU time,
3debabd9 331enabling a "Denial of Service" attack against Perl. Such hashes may be
504f80c1 332a problem for example for mod_perl sites, sites with Perl CGI scripts
333and web services, that process data originating from external sources.
334
86358043 335In Perl 5.8.1 a security feature was introduced to make it harder to
336create such degenerate hashes. A visible side effect of this was that
337the keys(), values(), and each() functions may return the hash elements
338in different order between different runs of Perl even with the same
339data. It also had unintended binary incompatibility issues with
340certain modules compiled against Perl 5.8.0.
341
342In Perl 5.8.2 an improved scheme was introduced. Hashes will return
343elements in the same order as Perl 5.8.0 by default. On a hash by hash
344basis, if pathological data is detected during a hash key insertion,
345then that hash will switch to an alternative random hash seed. As
346adding keys can always dramatically change returned hash element order,
347existing programs will not be affected by this, unless they
348specifically test for pre-recorded hash return order for contrived
349data. (eg the list of keys generated by C<map {"\0"x$_} 0..15> trigger
350randomisation) In effect the new implementation means that 5.8.1 scheme
351is only being used on hashes which are under attack.
352
353One can still revert to the old guaranteed repeatable order (and be
354vulnerable to attack by wily crackers) by setting the environment
355variable PERL_HASH_SEED, see L<perlrun/PERL_HASH_SEED>. Another option
356is to add -DUSE_HASH_SEED_EXPLICIT to the compilation flags (for
f80da78e 357example by using C<Configure -Accflags=-DUSE_HASH_SEED_EXPLICIT>), in
86358043 358which case one has to explicitly set the PERL_HASH_SEED environment
359variable to enable the security feature, or by adding -DNO_HASH_SEED to
360the compilation flags to completely disable the randomisation feature.
504f80c1 361
3debabd9 362B<Perl has never guaranteed any ordering of the hash keys>, and the
86358043 363ordering has already changed several times during the lifetime of Perl
3645. Also, the ordering of hash keys has always been, and continues to
08854360 365be, affected by the insertion order. Note that because of this
86358043 366randomisation for example the Data::Dumper results will be different
08854360 367between different runs of Perl, since Data::Dumper by default dumps
86358043 368hashes "unordered". The use of the Data::Dumper C<Sortkeys> option is
369recommended.
504f80c1 370
ce80d64e 371=head3 SOCKS
1b9c9cf5 372
373Perl can be configured to be 'socksified', that is, to use the SOCKS
374TCP/IP proxy protocol library. SOCKS is used to give applications
375access to transport layer network proxies. Perl supports only SOCKS
71c4561b 376Version 5. The corresponding Configure option is -Dusesocks.
377You can find more about SOCKS from wikipedia at
378L<http://en.wikipedia.org/wiki/SOCKS>.
1b9c9cf5 379
ce80d64e 380=head3 Dynamic Loading
d6baa268 381
71c4561b 382By default, Configure will compile perl to use dynamic loading.
383If you want to force perl to be compiled completely
d6baa268 384statically, you can either choose this when Configure prompts you or
385you can use the Configure command line option -Uusedl.
7df75831 386With this option, you won't be able to use any new extension
387(XS) module without recompiling perl itself.
d6baa268 388
ce80d64e 389=head3 Building a shared Perl library
c3edaffb 390
391Currently, for most systems, the main perl executable is built by
392linking the "perl library" libperl.a with perlmain.o, your static
8ba4bff0 393extensions, and various extra libraries, such as -lm.
c3edaffb 394
08854360 395On systems that support dynamic loading, it may be possible to
9d67150a 396replace libperl.a with a shared libperl.so. If you anticipate building
c3edaffb 397several different perl binaries (e.g. by embedding libperl into
398different programs, or by using the optional compiler extension), then
9d67150a 399you might wish to build a shared libperl.so so that all your binaries
c3edaffb 400can share the same library.
401
402The disadvantages are that there may be a significant performance
9d67150a 403penalty associated with the shared libperl.so, and that the overall
aa689395 404mechanism is still rather fragile with respect to different versions
c3edaffb 405and upgrades.
406
407In terms of performance, on my test system (Solaris 2.5_x86) the perl
9d67150a 408test suite took roughly 15% longer to run with the shared libperl.so.
c3edaffb 409Your system and typical applications may well give quite different
410results.
411
412The default name for the shared library is typically something like
08854360 413libperl.so.5.8.8 (for Perl 5.8.8), or libperl.so.588, or simply
9d67150a 414libperl.so. Configure tries to guess a sensible naming convention
c3edaffb 415based on your C library name. Since the library gets installed in a
416version-specific architecture-dependent directory, the exact name
417isn't very important anyway, as long as your linker is happy.
418
c3edaffb 419You can elect to build a shared libperl by
420
ce80d64e 421 sh Configure -Duseshrplib
422
423To build a shared libperl, the environment variable controlling shared
424library search (LD_LIBRARY_PATH in most systems, DYLD_LIBRARY_PATH for
425NeXTSTEP/OPENSTEP/Darwin, LIBRARY_PATH for BeOS, LD_LIBRARY_PATH/SHLIB_PATH
426for HP-UX, LIBPATH for AIX, PATH for Cygwin) must be set up to include
427the Perl build directory because that's where the shared libperl will
428be created. Configure arranges makefile to have the correct shared
429library search settings. You can find the name of the environment
430variable Perl thinks works in your your system by
431
432 grep ldlibpthname config.sh
433
434However, there are some special cases where manually setting the
435shared library path might be required. For example, if you want to run
436something like the following with the newly-built but not-yet-installed
437./perl:
438
08854360 439 cd t; ./perl -MTestInit misc/failing_test.t
440
ce80d64e 441or
08854360 442
ce80d64e 443 ./perl -Ilib ~/my_mission_critical_test
444
445then you need to set up the shared library path explicitly.
446You can do this with
447
448 LD_LIBRARY_PATH=`pwd`:$LD_LIBRARY_PATH; export LD_LIBRARY_PATH
449
450for Bourne-style shells, or
451
452 setenv LD_LIBRARY_PATH `pwd`
453
454for Csh-style shells. (This procedure may also be needed if for some
455unexpected reason Configure fails to set up makefile correctly.) (And
456again, it may be something other than LD_LIBRARY_PATH for you, see above.)
457
458You can often recognize failures to build/use a shared libperl from error
459messages complaining about a missing libperl.so (or libperl.sl in HP-UX),
460for example:
08854360 461
462 18126:./miniperl: /sbin/loader: Fatal Error: cannot map libperl.so
ce80d64e 463
464There is also an potential problem with the shared perl library if you
465want to have more than one "flavor" of the same version of perl (e.g.
466with and without -DDEBUGGING). For example, suppose you build and
08854360 467install a standard Perl 5.10.0 with a shared library. Then, suppose you
468try to build Perl 5.10.0 with -DDEBUGGING enabled, but everything else
ce80d64e 469the same, including all the installation directories. How can you
470ensure that your newly built perl will link with your newly built
471libperl.so.8 rather with the installed libperl.so.8? The answer is
472that you might not be able to. The installation directory is encoded
473in the perl binary with the LD_RUN_PATH environment variable (or
474equivalent ld command-line option). On Solaris, you can override that
475with LD_LIBRARY_PATH; on Linux, you can only override at runtime via
476LD_PRELOAD, specifying the exact filename you wish to be used; and on
477Digital Unix, you can override LD_LIBRARY_PATH by setting the
478_RLD_ROOT environment variable to point to the perl build directory.
479
480In other words, it is generally not a good idea to try to build a perl
481with a shared library if $archlib/CORE/$libperl already exists from a
482previous build.
483
484A good workaround is to specify a different directory for the
485architecture-dependent library for your -DDEBUGGING version of perl.
486You can do this by changing all the *archlib* variables in config.sh to
487point to your new architecture-dependent library.
488
575e1338 489=head3 Environment access
490
491Perl often needs to write to the program's environment, such as when C<%ENV>
492is assigned to. Many implementations of the C library function C<putenv()>
493leak memory, so where possible perl will manipulate the environment directly
494to avoid these leaks. The default is now to perform direct manipulation
495whenever perl is running as a stand alone interpreter, and to call the safe
496but potentially leaky C<putenv()> function when the perl interpreter is
497embedded in another application. You can force perl to always use C<putenv()>
779ec477 498by compiling with -DPERL_USE_SAFE_PUTENV. You can force an embedded perl to
575e1338 499use direct manipulation by setting C<PL_use_safe_putenv = 0;> after the
500C<perl_construct()> call.
501
ce80d64e 502=head2 Installation Directories
503
504The installation directories can all be changed by answering the
be8498a1 505appropriate questions in Configure. For convenience, all the installation
506questions are near the beginning of Configure. Do not include trailing
507slashes on directory names. At any point during the Configure process,
508you can answer a question with &-d and Configure will use the defaults
509from then on. Alternatively, you can
ce80d64e 510
511 grep '^install' config.sh
512
513after Configure has run to verify the installation paths.
514
515The defaults are intended to be reasonable and sensible for most
516people building from sources. Those who build and distribute binary
517distributions or who export perl to a range of systems will probably
518need to alter them. If you are content to just accept the defaults,
519you can safely skip the next section.
520
521The directories set up by Configure fall into three broad categories.
522
523=over 4
524
525=item Directories for the perl distribution
526
08854360 527By default, Configure will use the following directories for 5.10.0.
ce80d64e 528$version is the full perl version number, including subversion, e.g.
08854360 5295.10.0 or 5.9.5, and $archname is a string like sun4-sunos,
ce80d64e 530determined by Configure. The full definitions of all Configure
531variables are in the file Porting/Glossary.
532
533 Configure variable Default value
534 $prefixexp /usr/local
535 $binexp $prefixexp/bin
536 $scriptdirexp $prefixexp/bin
537 $privlibexp $prefixexp/lib/perl5/$version
538 $archlibexp $prefixexp/lib/perl5/$version/$archname
539 $man1direxp $prefixexp/man/man1
540 $man3direxp $prefixexp/man/man3
541 $html1direxp (none)
542 $html3direxp (none)
543
544$prefixexp is generated from $prefix, with ~ expansion done to convert home
545directories into absolute paths. Similarly for the other variables listed. As
546file system calls do not do this, you should always reference the ...exp
547variables, to support users who build perl in their home directory.
548
549Actually, Configure recognizes the SVR3-style
550/usr/local/man/l_man/man1 directories, if present, and uses those
551instead. Also, if $prefix contains the string "perl", the library
552directories are simplified as described below. For simplicity, only
553the common style is shown here.
554
555=item Directories for site-specific add-on files
556
557After perl is installed, you may later wish to add modules (e.g. from
558CPAN) or scripts. Configure will set up the following directories to
559be used for installing those add-on modules and scripts.
560
561 Configure variable Default value
562 $siteprefixexp $prefixexp
563 $sitebinexp $siteprefixexp/bin
564 $sitescriptexp $siteprefixexp/bin
565 $sitelibexp $siteprefixexp/lib/perl5/site_perl/$version
566 $sitearchexp $siteprefixexp/lib/perl5/site_perl/$version/$archname
567 $siteman1direxp $siteprefixexp/man/man1
568 $siteman3direxp $siteprefixexp/man/man3
569 $sitehtml1direxp (none)
570 $sitehtml3direxp (none)
571
572By default, ExtUtils::MakeMaker will install architecture-independent
573modules into $sitelib and architecture-dependent modules into $sitearch.
574
575=item Directories for vendor-supplied add-on files
576
577Lastly, if you are building a binary distribution of perl for
578distribution, Configure can optionally set up the following directories
579for you to use to distribute add-on modules.
580
581 Configure variable Default value
582 $vendorprefixexp (none)
583 (The next ones are set only if vendorprefix is set.)
584 $vendorbinexp $vendorprefixexp/bin
585 $vendorscriptexp $vendorprefixexp/bin
586 $vendorlibexp
587 $vendorprefixexp/lib/perl5/vendor_perl/$version
588 $vendorarchexp
589 $vendorprefixexp/lib/perl5/vendor_perl/$version/$archname
590 $vendorman1direxp $vendorprefixexp/man/man1
591 $vendorman3direxp $vendorprefixexp/man/man3
592 $vendorhtml1direxp (none)
593 $vendorhtml3direxp (none)
594
595These are normally empty, but may be set as needed. For example,
596a vendor might choose the following settings:
597
598 $prefix /usr
599 $siteprefix /usr/local
600 $vendorprefix /usr
601
602This would have the effect of setting the following:
603
604 $binexp /usr/bin
605 $scriptdirexp /usr/bin
606 $privlibexp /usr/lib/perl5/$version
607 $archlibexp /usr/lib/perl5/$version/$archname
608 $man1direxp /usr/man/man1
609 $man3direxp /usr/man/man3
610
611 $sitebinexp /usr/local/bin
612 $sitescriptexp /usr/local/bin
613 $sitelibexp /usr/local/lib/perl5/site_perl/$version
614 $sitearchexp /usr/local/lib/perl5/site_perl/$version/$archname
615 $siteman1direxp /usr/local/man/man1
616 $siteman3direxp /usr/local/man/man3
617
618 $vendorbinexp /usr/bin
619 $vendorscriptexp /usr/bin
620 $vendorlibexp /usr/lib/perl5/vendor_perl/$version
621 $vendorarchexp /usr/lib/perl5/vendor_perl/$version/$archname
622 $vendorman1direxp /usr/man/man1
623 $vendorman3direxp /usr/man/man3
624
625Note how in this example, the vendor-supplied directories are in the
626/usr hierarchy, while the directories reserved for the end-user are in
627the /usr/local hierarchy.
628
629The entire installed library hierarchy is installed in locations with
630version numbers, keeping the installations of different versions distinct.
631However, later installations of Perl can still be configured to search the
632installed libraries corresponding to compatible earlier versions.
7df75831 633See L<"Coexistence with earlier versions of perl 5"> below for more details
ce80d64e 634on how Perl can be made to search older version directories.
635
636Of course you may use these directories however you see fit. For
637example, you may wish to use $siteprefix for site-specific files that
638are stored locally on your own disk and use $vendorprefix for
639site-specific files that are stored elsewhere on your organization's
640network. One way to do that would be something like
641
642 sh Configure -Dsiteprefix=/usr/local -Dvendorprefix=/usr/share/perl
643
644=item otherlibdirs
645
646As a final catch-all, Configure also offers an $otherlibdirs
647variable. This variable contains a colon-separated list of additional
648directories to add to @INC. By default, it will be empty.
649Perl will search these directories (including architecture and
650version-specific subdirectories) for add-on modules and extensions.
651
652For example, if you have a bundle of perl libraries from a previous
653installation, perhaps in a strange place:
654
655 Configure -Dotherlibdirs=/usr/lib/perl5/site_perl/5.8.1
656
657=item APPLLIB_EXP
658
659There is one other way of adding paths to @INC at perl build time, and
660that is by setting the APPLLIB_EXP C pre-processor token to a colon-
661separated list of directories, like this
662
663 sh Configure -Accflags='-DAPPLLIB_EXP=\"/usr/libperl\"'
664
665The directories defined by APPLLIB_EXP get added to @INC I<first>,
666ahead of any others, and so provide a way to override the standard perl
667modules should you, for example, want to distribute fixes without
668touching the perl distribution proper. And, like otherlib dirs,
669version and architecture specific subdirectories are also searched, if
670present, at run time. Of course, you can still search other @INC
671directories ahead of those in APPLLIB_EXP by using any of the standard
672run-time methods: $PERLLIB, $PERL5LIB, -I, use lib, etc.
673
785aa5e3 674=item usesitecustomize
20ef40cf 675
676Run-time customization of @INC can be enabled with:
677
36de116d 678 sh Configure -Dusesitecustomize
20ef40cf 679
785aa5e3 680which will define USE_SITECUSTOMIZE and $Config{usesitecustomize}.
681When enabled, this makes perl run F<$sitelibexp/sitecustomize.pl> before
20ef40cf 682anything else. This script can then be set up to add additional
683entries to @INC.
684
ce80d64e 685=item Man Pages
686
be8498a1 687By default, man pages will be installed in $man1dir and $man3dir, which
688are normally /usr/local/man/man1 and /usr/local/man/man3. If you
689want to use a .3pm suffix for perl man pages, you can do that with
ce80d64e 690
691 sh Configure -Dman3ext=3pm
692
ce80d64e 693=item HTML pages
694
695Currently, the standard perl installation does not do anything with
696HTML documentation, but that may change in the future. Further, some
697add-on modules may wish to install HTML documents. The html Configure
698variables listed above are provided if you wish to specify where such
699documents should be placed. The default is "none", but will likely
700eventually change to something useful based on user feedback.
701
702=back
703
704Some users prefer to append a "/share" to $privlib and $sitelib
705to emphasize that those directories can be shared among different
706architectures.
707
708Note that these are just the defaults. You can actually structure the
709directories any way you like. They don't even have to be on the same
710filesystem.
c3edaffb 711
ce80d64e 712Further details about the installation directories, maintenance and
713development subversions, and about supporting multiple versions are
7df75831 714discussed in L<"Coexistence with earlier versions of perl 5"> below.
10c7e831 715
ce80d64e 716If you specify a prefix that contains the string "perl", then the
717library directory structure is slightly simplified. Instead of
718suggesting $prefix/lib/perl5/, Configure will suggest $prefix/lib.
2bf2710f 719
ce80d64e 720Thus, for example, if you Configure with
721-Dprefix=/opt/perl, then the default library directories for 5.9.0 are
2bf2710f 722
ce80d64e 723 Configure variable Default value
724 $privlib /opt/perl/lib/5.9.0
725 $archlib /opt/perl/lib/5.9.0/$archname
726 $sitelib /opt/perl/lib/site_perl/5.9.0
727 $sitearch /opt/perl/lib/site_perl/5.9.0/$archname
2bf2710f 728
ce80d64e 729=head2 Changing the installation directory
c3edaffb 730
ce80d64e 731Configure distinguishes between the directory in which perl (and its
7df75831 732associated files) should be installed, and the directory in which it
ce80d64e 733will eventually reside. For most sites, these two are the same; for
734sites that use AFS, this distinction is handled automatically.
7df75831 735However, sites that use package management software such as rpm or
736dpkg, or users building binary packages for distribution may also
737wish to install perl into a different directory before moving perl
738to its final destination. There are two ways to do that:
739
740=over 4
741
742=item installprefix
c3edaffb 743
be8498a1 744To install perl under the /tmp/perl5 directory, use the following
745command line:
c3edaffb 746
7df75831 747 sh Configure -Dinstallprefix=/tmp/perl5
c3edaffb 748
ce80d64e 749(replace /tmp/perl5 by a directory of your choice).
2bf2710f 750
ce80d64e 751Beware, though, that if you go to try to install new add-on
752modules, they too will get installed in under '/tmp/perl5' if you
7df75831 753follow this example. That's why it's usually better to use DESTDIR,
754as shown in the next section.
c3edaffb 755
7df75831 756=item DESTDIR
9d67150a 757
ce80d64e 758If you need to install perl on many identical systems, it is convenient
759to compile it once and create an archive that can be installed on
760multiple systems. Suppose, for example, that you want to create an
761archive that can be installed in /opt/perl. One way to do that is by
762using the DESTDIR variable during C<make install>. The DESTDIR is
763automatically prepended to all the installation paths. Thus you
764simply do:
830717a7 765
ce80d64e 766 sh Configure -Dprefix=/opt/perl -des
767 make
768 make test
769 make install DESTDIR=/tmp/perl5
770 cd /tmp/perl5/opt/perl
771 tar cvf /tmp/perl5-archive.tar .
9d67150a 772
7df75831 773=back
774
32878f30 775=head2 Relocatable @INC
776
777To create a relocatable perl tree, use the following command line:
778
779 sh Configure -Duserelocatableinc
780
781Then the paths in @INC (and everything else in %Config) can be
782optionally located via the path of the perl executable.
783
784That means that, if the string ".../" is found at the start of any
785path, it's substituted with the directory of $^X. So, the relocation
786can be configured on a per-directory basis, although the default with
787"-Duserelocatableinc" is that everything is relocated. The initial
788install is done to the original configured prefix.
789
ce80d64e 790=head2 Site-wide Policy settings
55479bb6 791
ce80d64e 792After Configure runs, it stores a number of common site-wide "policy"
7df75831 793answers (such as installation directories) in the Policy.sh file.
794If you want to build perl on another system using the same policy
795defaults, simply copy the Policy.sh file to the new system's perl build
796directory, and Configure will use it. This will work even if Policy.sh was
a0a8d9d3 797generated for another version of Perl, or on a system with a
da1b4322 798different architecture and/or operating system. However, in such cases,
a0a8d9d3 799you should review the contents of the file before using it: for
800example, your new target may not keep its man pages in the same place
801as the system on which the file was generated.
55479bb6 802
ce80d64e 803Alternatively, if you wish to change some or all of those policy
804answers, you should
c3edaffb 805
ce80d64e 806 rm -f Policy.sh
aa689395 807
ce80d64e 808to ensure that Configure doesn't re-use them.
2ae324a7 809
ce80d64e 810Further information is in the Policy_sh.SH file itself.
aa689395 811
ce80d64e 812If the generated Policy.sh file is unsuitable, you may freely edit it
813to contain any valid shell commands. It will be run just after the
814platform-specific hints files.
aa689395 815
ce80d64e 816=head2 Disabling older versions of Perl
aa689395 817
ce80d64e 818Configure will search for binary compatible versions of previously
7df75831 819installed perl binaries in the tree that is specified as target tree,
820and these will be used as locations to search for modules by the perl
821being built. The list of perl versions found will be put in the Configure
822variable inc_version_list.
86058a2d 823
ce80d64e 824To disable this use of older perl modules, even completely valid pure perl
825modules, you can specify to not include the paths found:
b2a6d19e 826
ce80d64e 827 sh Configure -Dinc_version_list=none ...
d6baa268 828
ce80d64e 829When using the newer perl, you can add these paths again in the
830$PERL5LIB environment variable or with perl's -I runtime option.
86058a2d 831
ce80d64e 832=head2 Building Perl outside of the source directory
86058a2d 833
ce80d64e 834Sometimes it is desirable to build Perl in a directory different from
835where the sources are, for example if you want to keep your sources
836read-only, or if you want to share the sources between different binary
837architectures. You can do this (if your file system supports symbolic
838links) by
06c896bb 839
ce80d64e 840 mkdir /tmp/perl/build/directory
841 cd /tmp/perl/build/directory
842 sh /path/to/perl/source/Configure -Dmksymlinks ...
06c896bb 843
ce80d64e 844This will create in /tmp/perl/build/directory a tree of symbolic links
845pointing to files in /path/to/perl/source. The original files are left
846unaffected. After Configure has finished you can just say
06c896bb 847
ce80d64e 848 make
7df75831 849 make test
850 make install
06c896bb 851
ce80d64e 852as usual, and Perl will be built in /tmp/perl/build/directory.
aa689395 853
3bf462b8 854=head2 Building a debugging perl
855
856You can run perl scripts under the perl debugger at any time with
3fe9a6f1 857B<perl -d your_script>. If, however, you want to debug perl itself,
eaf812ae 858you probably want to have support for perl internal debugging code
859(activated by adding -DDEBUGGING to ccflags), and/or support for the
7df75831 860system debugger by adding -g to the optimisation flags. For that,
861use the parameter:
eaf812ae 862
08854360 863 sh Configure -DDEBUGGING
864
865or
866
eaf812ae 867 sh Configure -DDEBUGGING=<mode>
868
869For a more eye appealing call, -DEBUGGING is defined to be an alias
870for -DDEBUGGING. For both, the -U calls are also supported, in order
871to be able to overrule the hints or Policy.sh settings.
872
7df75831 873Here are the DEBUGGING modes:
3bf462b8 874
7df75831 875=over 4
3bf462b8 876
eaf812ae 877=item -DDEBUGGING
878
879=item -DEBUGGING
880
881=item -DEBUGGING=both
882
7df75831 883Sets both -DDEBUGGING in the ccflags, and adds -g to optimize.
884
885You can actually specify -g and -DDEBUGGING independently (see below),
886but usually it's convenient to have both.
eaf812ae 887
888=item -DEBUGGING=-g
889
7df75831 890=item -Doptimize=-g
891
eaf812ae 892Adds -g to optimize, but does not set -DDEBUGGING.
893
7df75831 894(Note: Your system may actually require something like cc -g2.
895Check your man pages for cc(1) and also any hint file for your system.)
896
eaf812ae 897=item -DEBUGGING=none
898
7df75831 899=item -UDEBUGGING
900
eaf812ae 901Removes -g from optimize, and -DDEBUGGING from ccflags.
902
903=back
904
3bf462b8 905If you are using a shared libperl, see the warnings about multiple
a522f097 906versions of perl under L<Building a shared Perl library>.
3bf462b8 907
8d74ce1c 908=head2 Extensions
909
80c1f5de 910Perl ships with a number of standard extensions. These are contained
911in the ext/ subdirectory.
912
8d74ce1c 913By default, Configure will offer to build every extension which appears
914to be supported. For example, Configure will offer to build GDBM_File
7df75831 915only if it is able to find the gdbm library.
ce80d64e 916
917To disable certain extensions so that they are not built, use the
918-Dnoextensions=... and -Donlyextensions=... options. They both accept
919a space-separated list of extensions. The extensions listed in
920C<noextensions> are removed from the list of extensions to build, while
921the C<onlyextensions> is rather more severe and builds only the listed
922extensions. The latter should be used with extreme caution since
923certain extensions are used by many other extensions and modules:
924examples of such modules include Fcntl and IO. The order of processing
925these options is first C<only> (if present), then C<no> (if present).
8d74ce1c 926
927Of course, you may always run Configure interactively and select only
928the extensions you want.
929
7df75831 930If you unpack any additional extensions in the ext/ directory before
931running Configure, then Configure will offer to build those additional
932extensions as well. Most users probably shouldn't have to do this --
933it is usually easier to build additional extensions later after perl
934has been installed. However, if you wish to have those additional
935extensions statically linked into the perl binary, then this offers a
936convenient way to do that in one step. (It is not necessary, however;
937you can build and install extensions just fine even if you don't have
938dynamic loading. See lib/ExtUtils/MakeMaker.pm for more details.)
939Another way of specifying extra modules is described in
940L<"Adding extra modules to the build"> below.
8d74ce1c 941
dd3196cd 942If you re-use an old config.sh but change your system (e.g. by
8d74ce1c 943adding libgdbm) Configure will still offer your old choices of extensions
944for the default answer, but it will also point out the discrepancy to
945you.
946
8d74ce1c 947=head2 Including locally-installed libraries
948
7df75831 949Perl comes with interfaces to number of libraries, including threads,
950dbm, ndbm, gdbm, and Berkeley db. For the *db* extension, if
8d74ce1c 951Configure can find the appropriate header files and libraries, it will
7df75831 952automatically include that extension. The threading extension needs
953to be specified explicitely (see L<Threads>).
954
955Those libraries are not distributed with perl. If your header (.h) files
956for those libraries are not in a directory normally searched by your C
957compiler, then you will need to include the appropriate -I/your/directory
958option when prompted by Configure. If your libraries are not in a
959directory normally searched by your C compiler and linker, then you will
960need to include the appropriate -L/your/directory option when prompted
961by Configure. See the examples below.
8d74ce1c 962
ce80d64e 963=head3 Examples
8d74ce1c 964
965=over 4
966
967=item gdbm in /usr/local
968
969Suppose you have gdbm and want Configure to find it and build the
d6baa268 970GDBM_File extension. This example assumes you have gdbm.h
8d74ce1c 971installed in /usr/local/include/gdbm.h and libgdbm.a installed in
972/usr/local/lib/libgdbm.a. Configure should figure all the
973necessary steps out automatically.
974
975Specifically, when Configure prompts you for flags for
7df75831 976your C compiler, you should include -I/usr/local/include, if it's
977not here yet. Similarly, when Configure prompts you for linker flags,
978you should include -L/usr/local/lib.
8d74ce1c 979
980If you are using dynamic loading, then when Configure prompts you for
981linker flags for dynamic loading, you should again include
982-L/usr/local/lib.
983
d6baa268 984Again, this should all happen automatically. This should also work if
985you have gdbm installed in any of (/usr/local, /opt/local, /usr/gnu,
986/opt/gnu, /usr/GNU, or /opt/GNU).
8d74ce1c 987
e8b9ce60 988=item BerkeleyDB in /usr/local/BerkeleyDB
989
990The version of BerkeleyDB distributed by sleepycat.com installs in a
991version-specific directory by default, typically something like
992/usr/local/BerkeleyDB.4.7. To have Configure find that, you need to add
993-I/usr/local/BerkeleyDB.4.7/include to cc flags, as in the previous example,
994and you will also have to take extra steps to help Configure find -ldb.
995Specifically, when Configure prompts you for library directories,
996add /usr/local/BerkeleyDB.4.7/lib to the list. Also, you will need to
997add appropriate linker flags to tell the runtime linker where to find the
998BerkeleyDB shared libraries.
999
1000It is possible to specify this from the command line (all on one
8d74ce1c 1001line):
1002
7df75831 1003 sh Configure -de \
e8b9ce60 1004 -Dlocincpth='/usr/local/BerkeleyDB.4.7/include /usr/local/include' \
1005 -Dloclibpth='/usr/local/BerkeleyDB.4.7/lib /usr/local/lib' \
1006 -Aldflags='-R/usr/local/BerkeleyDB.4.7/lib'
8d74ce1c 1007
1008locincpth is a space-separated list of include directories to search.
1009Configure will automatically add the appropriate -I directives.
1010
1011loclibpth is a space-separated list of library directories to search.
e8b9ce60 1012Configure will automatically add the appropriate -L directives.
8d74ce1c 1013
e8b9ce60 1014The addition to ldflags is so that the dynamic linker knows where to find
1015the BerkeleyDB libraries. For Linux and Solaris, the -R option does that.
1016Other systems may use different flags. Use the appropriate flag for your
1017system.
8d74ce1c 1018
1019=back
1020
ce80d64e 1021=head2 Overriding an old config.sh
1022
dd3196cd 1023If you want to use an old config.sh produced by a previous run of
1024Configure, but override some of the items with command line options, you
1025need to use B<Configure -O>.
ce80d64e 1026
1027=head2 GNU-style configure
1028
1029If you prefer the GNU-style configure command line interface, you can
1030use the supplied configure.gnu command, e.g.
1031
1032 CC=gcc ./configure.gnu
1033
1034The configure.gnu script emulates a few of the more common configure
1035options. Try
1036
1037 ./configure.gnu --help
1038
1039for a listing.
1040
1041(The file is called configure.gnu to avoid problems on systems
1042that would not distinguish the files "Configure" and "configure".)
1043
ce80d64e 1044=head2 Malloc Issues
1045
1046Perl relies heavily on malloc(3) to grow data structures as needed,
1047so perl's performance can be noticeably affected by the performance of
1048the malloc function on your system. The perl source is shipped with a
1049version of malloc that has been optimized for the typical requests from
1050perl, so there's a chance that it may be both faster and use less memory
1051than your system malloc.
1052
1053However, if your system already has an excellent malloc, or if you are
1054experiencing difficulties with extensions that use third-party libraries
1055that call malloc, then you should probably use your system's malloc.
1056(Or, you might wish to explore the malloc flags discussed below.)
1057
1058=over 4
1059
1060=item Using the system malloc
1061
1062To build without perl's malloc, you can use the Configure command
1063
1064 sh Configure -Uusemymalloc
1065
1066or you can answer 'n' at the appropriate interactive Configure prompt.
1067
73d6d1b0 1068Note that Perl's malloc isn't always used by default; that actually
1069depends on your system. For example, on Linux and FreeBSD (and many more
1070systems), Configure chooses to use the system's malloc by default.
1071See the appropriate file in the F<hints/> directory to see how the
1072default is set.
1073
ce80d64e 1074=item -DPERL_POLLUTE_MALLOC
1075
1076NOTE: This flag is enabled automatically on some platforms if you just
7df75831 1077run Configure to accept all the defaults.
ce80d64e 1078
1079Perl's malloc family of functions are normally called Perl_malloc(),
1080Perl_realloc(), Perl_calloc() and Perl_mfree().
1081These names do not clash with the system versions of these functions.
1082
1083If this flag is enabled, however, Perl's malloc family of functions
1084will have the same names as the system versions. This may be required
1085sometimes if you have libraries that like to free() data that may have
1086been allocated by Perl_malloc() and vice versa.
1087
1088Note that enabling this option may sometimes lead to duplicate symbols
1089from the linker for malloc et al. In such cases, the system probably
1090does not allow its malloc functions to be fully replaced with custom
1091versions.
1092
1093=item -DPERL_DEBUGGING_MSTATS
1094
1095This flag enables debugging mstats, which is required to use the
1096Devel::Peek::mstat() function. You cannot enable this unless you are
1097using Perl's malloc, so a typical Configure command would be
1098
7df75831 1099 sh Configure -Accflags=-DPERL_DEBUGGING_MSTATS -Dusemymalloc
ce80d64e 1100
1101to enable this option.
1102
1103=back
1104
8e07c86e 1105=head2 What if it doesn't work?
1106
8d74ce1c 1107If you run into problems, try some of the following ideas.
ff52061e 1108If none of them help, then see L<"Reporting Problems"> below.
8d74ce1c 1109
8e07c86e 1110=over 4
1111
25f94b33 1112=item Running Configure Interactively
1113
1114If Configure runs into trouble, remember that you can always run
1115Configure interactively so that you can check (and correct) its
1116guesses.
1117
1118All the installation questions have been moved to the top, so you don't
aa689395 1119have to wait for them. Once you've handled them (and your C compiler and
1ec51d55 1120flags) you can type &-d at the next Configure prompt and Configure
25f94b33 1121will use the defaults from then on.
1122
1123If you find yourself trying obscure command line incantations and
1124config.over tricks, I recommend you run Configure interactively
1125instead. You'll probably save yourself time in the long run.
1126
aa689395 1127=item Hint files
8e07c86e 1128
a0a8d9d3 1129Hint files tell Configure about a number of things:
1130
1131=over 4
1132
1133=item o
1134
1135The peculiarities or conventions of particular platforms -- non-standard
1136library locations and names, default installation locations for binaries,
1137and so on.
1138
1139=item o
1140
1141The deficiencies of the platform -- for example, library functions that,
1142although present, are too badly broken to be usable; or limits on
1143resources that are generously available on most platforms.
1144
1145=item o
1146
1147How best to optimize for the platform, both in terms of binary size and/or
1148speed, and for Perl feature support. Because of wide variations in the
1149implementation of shared libraries and of threading, for example, Configure
1150often needs hints in order to be able to use these features.
1151
1152=back
1153
1154The perl distribution includes many system-specific hints files
1155in the hints/ directory. If one of them matches your system, Configure
1156will offer to use that hint file. Unless you have a very good reason
1157not to, you should accept its offer.
8e07c86e 1158
1159Several of the hint files contain additional important information.
f5b3b617 1160If you have any problems, it is a good idea to read the relevant hint file
1161for further information. See hints/solaris_2.sh for an extensive example.
1162More information about writing good hints is in the hints/README.hints
a0a8d9d3 1163file, which also explains hint files known as callback-units.
1164
1165Note that any hint file is read before any Policy file, meaning that
1166Policy overrides hints -- see L</Site-wide Policy settings>.
8e07c86e 1167
73d6d1b0 1168=item WHOA THERE!!!
edb1cbcb 1169
82c11e95 1170If you are re-using an old config.sh, it's possible that Configure detects
1171different values from the ones specified in this file. You will almost
1172always want to keep the previous value, unless you have changed something
1173on your system.
edb1cbcb 1174
1175For example, suppose you have added libgdbm.a to your system
1176and you decide to reconfigure perl to use GDBM_File. When you run
1177Configure again, you will need to add -lgdbm to the list of libraries.
bfb7748a 1178Now, Configure will find your gdbm include file and library and will
1179issue a message:
edb1cbcb 1180
1181 *** WHOA THERE!!! ***
1182 The previous value for $i_gdbm on this machine was "undef"!
1183 Keep the previous value? [y]
1184
1ec51d55 1185In this case, you do not want to keep the previous value, so you
c3edaffb 1186should answer 'n'. (You'll also have to manually add GDBM_File to
edb1cbcb 1187the list of dynamic extensions to build.)
1188
8e07c86e 1189=item Changing Compilers
1190
1191If you change compilers or make other significant changes, you should
1ec51d55 1192probably not re-use your old config.sh. Simply remove it or
dd3196cd 1193rename it, then rerun Configure with the options you want to use.
8e07c86e 1194
c3edaffb 1195=item Propagating your changes to config.sh
8e07c86e 1196
1ec51d55 1197If you make any changes to config.sh, you should propagate
1198them to all the .SH files by running
1199
1200 sh Configure -S
1201
1202You will then have to rebuild by running
9d67150a 1203
1204 make depend
1205 make
8e07c86e 1206
48370efc 1207=item config.over and config.arch
1208
1209You can also supply a shell script config.over to over-ride
1210Configure's guesses. It will get loaded up at the very end, just
1211before config.sh is created. You have to be careful with this,
1212however, as Configure does no checking that your changes make sense.
1213This file is usually good for site-specific customizations.
1214
1215There is also another file that, if it exists, is loaded before the
1216config.over, called config.arch. This file is intended to be per
1217architecture, not per site, and usually it's the architecture-specific
1218hints file that creates the config.arch.
8e07c86e 1219
1220=item config.h
1221
1ec51d55 1222Many of the system dependencies are contained in config.h.
1223Configure builds config.h by running the config_h.SH script.
1224The values for the variables are taken from config.sh.
8e07c86e 1225
1ec51d55 1226If there are any problems, you can edit config.h directly. Beware,
1227though, that the next time you run Configure, your changes will be
8e07c86e 1228lost.
1229
1230=item cflags
1231
1232If you have any additional changes to make to the C compiler command
1ec51d55 1233line, they can be made in cflags.SH. For instance, to turn off the
1234optimizer on toke.c, find the line in the switch structure for
1235toke.c and put the command optimize='-g' before the ;; . You
1236can also edit cflags directly, but beware that your changes will be
1237lost the next time you run Configure.
8e07c86e 1238
f5b3b617 1239To explore various ways of changing ccflags from within a hint file,
1240see the file hints/README.hints.
1241
1242To change the C flags for all the files, edit config.sh and change either
1243$ccflags or $optimize, and then re-run
1ec51d55 1244
1245 sh Configure -S
1246 make depend
8e07c86e 1247
aa689395 1248=item No sh
8e07c86e 1249
c42e3e15 1250If you don't have sh, you'll have to copy the sample file
1251Porting/config.sh to config.sh and edit your config.sh to reflect your
1252system's peculiarities. See Porting/pumpkin.pod for more information.
8e07c86e 1253You'll probably also have to extensively modify the extension building
1254mechanism.
1255
c3edaffb 1256=item Porting information
1257
e6f03d26 1258Specific information for the OS/2, Plan 9, VMS and Win32 ports is in the
1ec51d55 1259corresponding README files and subdirectories. Additional information,
1260including a glossary of all those config.sh variables, is in the Porting
ce80d64e 1261subdirectory. Porting/Glossary should especially come in handy.
c3edaffb 1262
7f678428 1263Ports for other systems may also be available. You should check out
468f45d5 1264http://www.cpan.org/ports for current information on ports to
7f678428 1265various other operating systems.
1266
ce80d64e 1267If you plan to port Perl to a new architecture, study carefully the
491517e0 1268section titled "Philosophical Issues in Patching and Porting Perl"
1269in the file Porting/pumpkin.pod and the file Porting/patching.pod.
1270Study also how other non-UNIX ports have solved problems.
1271
8e07c86e 1272=back
1273
ce80d64e 1274=head2 Adding extra modules to the build
fadf0ef5 1275
1276You can specify extra modules or module bundles to be fetched from the
1277CPAN and installed as part of the Perl build. Either use the -Dextras=...
1278command line parameter to Configure, for example like this:
1279
d3df0cfd 1280 Configure -Dextras="Bundle::LWP DBI"
fadf0ef5 1281
1282or answer first 'y' to the question 'Install any extra modules?' and
d3df0cfd 1283then answer "Bundle::LWP DBI" to the 'Extras?' question.
fadf0ef5 1284The module or the bundle names are as for the CPAN module 'install' command.
a522f097 1285This will only work if those modules are to be built as dynamic
1286extensions. If you wish to include those extra modules as static
1287extensions, see L<"Extensions"> above.
fadf0ef5 1288
1289Notice that because the CPAN module will be used to fetch the extra
1290modules, you will need access to the CPAN, either via the Internet,
1291or via a local copy such as a CD-ROM or a local CPAN mirror. If you
1292do not, using the extra modules option will die horribly.
1293
1294Also notice that you yourself are responsible for satisfying any extra
1295dependencies such as external headers or libraries BEFORE trying the build.
d3df0cfd 1296For example: you will need to have the Foo database specific
fadf0ef5 1297headers and libraries installed for the DBD::Foo module. The Configure
1298process or the Perl build process will not help you with these.
1299
ce80d64e 1300=head2 suidperl
03739d21 1301
ce80d64e 1302suidperl is an optional component, which is normally neither built
1303nor installed by default. From perlfaq1:
03739d21 1304
1305 On some systems, setuid and setgid scripts (scripts written
1306 in the C shell, Bourne shell, or Perl, for example, with the
1307 set user or group ID permissions enabled) are insecure due to
1308 a race condition in the kernel. For those systems, Perl versions
1309 5 and 4 attempt to work around this vulnerability with an optional
1310 component, a special program named suidperl, also known as sperl.
1311 This program attempts to emulate the set-user-ID and set-group-ID
1312 features of the kernel.
1313
1314Because of the buggy history of suidperl, and the difficulty
1315of properly security auditing as large and complex piece of
1316software as Perl, we cannot recommend using suidperl and the feature
1317should be considered deprecated.
08854360 1318
ce80d64e 1319Instead, use a tool specifically designed to handle changes in
08854360 1320privileges, such as B<sudo>.
03739d21 1321
8e07c86e 1322=head1 make depend
1323
bfb7748a 1324This will look for all the includes. The output is stored in makefile.
1325The only difference between Makefile and makefile is the dependencies at
1326the bottom of makefile. If you have to make any changes, you should edit
ce80d64e 1327makefile, not Makefile, since the Unix make command reads makefile first.
bfb7748a 1328(On non-Unix systems, the output may be stored in a different file.
1329Check the value of $firstmakefile in your config.sh if in doubt.)
8e07c86e 1330
1331Configure will offer to do this step for you, so it isn't listed
1332explicitly above.
1333
1334=head1 make
1335
1336This will attempt to make perl in the current directory.
1337
8d410bc4 1338=head2 Expected errors
1339
f5b5f377 1340These error reports are normal, and can be ignored:
8d410bc4 1341
1342 ...
1343 make: [extra.pods] Error 1 (ignored)
1344 ...
1345 make: [extras.make] Error 1 (ignored)
1346
8d74ce1c 1347=head2 What if it doesn't work?
1348
8e07c86e 1349If you can't compile successfully, try some of the following ideas.
7f678428 1350If none of them help, and careful reading of the error message and
8d74ce1c 1351the relevant manual pages on your system doesn't help,
ff52061e 1352then see L<"Reporting Problems"> below.
8e07c86e 1353
1354=over 4
1355
1ec51d55 1356=item hints
8e07c86e 1357
1358If you used a hint file, try reading the comments in the hint file
1359for further tips and information.
1360
1ec51d55 1361=item extensions
8e07c86e 1362
1ec51d55 1363If you can successfully build miniperl, but the process crashes
ce80d64e 1364during the building of extensions, run
c3edaffb 1365
3a6175e1 1366 make minitest
c3edaffb 1367
1368to test your version of miniperl.
1369
e57fd563 1370=item locale
1371
bfb7748a 1372If you have any locale-related environment variables set, try unsetting
1373them. I have some reports that some versions of IRIX hang while
1374running B<./miniperl configpm> with locales other than the C locale.
1375See the discussion under L<"make test"> below about locales and the
08854360 1376whole L<perllocale/"LOCALE PROBLEMS"> section in the file pod/perllocale.pod.
3e6e419a 1377The latter is especially useful if you see something like this
1378
1379 perl: warning: Setting locale failed.
1380 perl: warning: Please check that your locale settings:
1381 LC_ALL = "En_US",
1382 LANG = (unset)
1383 are supported and installed on your system.
1384 perl: warning: Falling back to the standard locale ("C").
1385
1386at Perl startup.
e57fd563 1387
7f678428 1388=item varargs
c3edaffb 1389
1390If you get varargs problems with gcc, be sure that gcc is installed
bfb7748a 1391correctly and that you are not passing -I/usr/include to gcc. When using
1392gcc, you should probably have i_stdarg='define' and i_varargs='undef'
ce80d64e 1393in config.sh. The problem is usually solved by installing gcc
bfb7748a 1394correctly. If you do change config.sh, don't forget to propagate
1395your changes (see L<"Propagating your changes to config.sh"> below).
7f678428 1396See also the L<"vsprintf"> item below.
c3edaffb 1397
bfb7748a 1398=item util.c
c3edaffb 1399
1400If you get error messages such as the following (the exact line
bfb7748a 1401numbers and function name may vary in different versions of perl):
c3edaffb 1402
bfb7748a 1403 util.c: In function `Perl_form':
1404 util.c:1107: number of arguments doesn't match prototype
1405 proto.h:125: prototype declaration
c3edaffb 1406
1407it might well be a symptom of the gcc "varargs problem". See the
7f678428 1408previous L<"varargs"> item.
c3edaffb 1409
1ec51d55 1410=item LD_LIBRARY_PATH
c3edaffb 1411
1412If you run into dynamic loading problems, check your setting of
aa689395 1413the LD_LIBRARY_PATH environment variable. If you're creating a static
1414Perl library (libperl.a rather than libperl.so) it should build
c3edaffb 1415fine with LD_LIBRARY_PATH unset, though that may depend on details
1416of your local set-up.
1417
aa689395 1418=item nm extraction
c3edaffb 1419
1420If Configure seems to be having trouble finding library functions,
1421try not using nm extraction. You can do this from the command line
1422with
1423
1424 sh Configure -Uusenm
1425
1426or by answering the nm extraction question interactively.
1ec51d55 1427If you have previously run Configure, you should not reuse your old
c3edaffb 1428config.sh.
1429
bfb7748a 1430=item umask not found
1431
1432If the build processes encounters errors relating to umask(), the problem
1433is probably that Configure couldn't find your umask() system call.
1434Check your config.sh. You should have d_umask='define'. If you don't,
1435this is probably the L<"nm extraction"> problem discussed above. Also,
1436try reading the hints file for your system for further information.
1437
7f678428 1438=item vsprintf
c3edaffb 1439
1440If you run into problems with vsprintf in compiling util.c, the
1441problem is probably that Configure failed to detect your system's
1442version of vsprintf(). Check whether your system has vprintf().
1443(Virtually all modern Unix systems do.) Then, check the variable
1444d_vprintf in config.sh. If your system has vprintf, it should be:
1445
1446 d_vprintf='define'
1447
1448If Configure guessed wrong, it is likely that Configure guessed wrong
bfb7748a 1449on a number of other common functions too. This is probably
1450the L<"nm extraction"> problem discussed above.
c3edaffb 1451
3fe9a6f1 1452=item do_aspawn
1453
1454If you run into problems relating to do_aspawn or do_spawn, the
1455problem is probably that Configure failed to detect your system's
bfb7748a 1456fork() function. Follow the procedure in the previous item
1457on L<"nm extraction">.
3fe9a6f1 1458
84902520 1459=item __inet_* errors
1460
1461If you receive unresolved symbol errors during Perl build and/or test
1462referring to __inet_* symbols, check to see whether BIND 8.1 is
1463installed. It installs a /usr/local/include/arpa/inet.h that refers to
1464these symbols. Versions of BIND later than 8.1 do not install inet.h
1465in that location and avoid the errors. You should probably update to a
6d240721 1466newer version of BIND (and remove the files the old one left behind).
1467If you can't, you can either link with the updated resolver library provided
1468with BIND 8.1 or rename /usr/local/bin/arpa/inet.h during the Perl build and
1469test process to avoid the problem.
1470
73d6d1b0 1471=item .*_r() prototype NOT found
6d240721 1472
1473On a related note, if you see a bunch of complaints like the above about
1474reentrant functions - specifically networking-related ones - being present
1475but without prototypes available, check to see if BIND 8.1 (or possibly
1476other BIND 8 versions) is (or has been) installed. They install
1477header files such as netdb.h into places such as /usr/local/include (or into
1478another directory as specified at build/install time), at least optionally.
f1300be0 1479Remove them or put them in someplace that isn't in the C preprocessor's
6d240721 1480header file include search path (determined by -I options plus defaults,
1481normally /usr/include).
84902520 1482
d6baa268 1483=item #error "No DATAMODEL_NATIVE specified"
1484
1485This is a common error when trying to build perl on Solaris 2.6 with a
1486gcc installation from Solaris 2.5 or 2.5.1. The Solaris header files
1487changed, so you need to update your gcc installation. You can either
1488rerun the fixincludes script from gcc or take the opportunity to
1489update your gcc installation.
1490
aa689395 1491=item Optimizer
c3edaffb 1492
9d67150a 1493If you can't compile successfully, try turning off your compiler's
aa689395 1494optimizer. Edit config.sh and change the line
9d67150a 1495
1496 optimize='-O'
1497
bfb7748a 1498to
9d67150a 1499
1500 optimize=' '
1501
1502then propagate your changes with B<sh Configure -S> and rebuild
1503with B<make depend; make>.
1504
4bbc1586 1505=item Missing functions and Undefined symbols
9d67150a 1506
4bbc1586 1507If the build of miniperl fails with a long list of missing functions or
1508undefined symbols, check the libs variable in the config.sh file. It
1509should look something like
1510
1511 libs='-lsocket -lnsl -ldl -lm -lc'
1512
1513The exact libraries will vary from system to system, but you typically
1514need to include at least the math library -lm. Normally, Configure
1515will suggest the correct defaults. If the libs variable is empty, you
1516need to start all over again. Run
1517
1518 make distclean
1519
1520and start from the very beginning. This time, unless you are sure of
1521what you are doing, accept the default list of libraries suggested by
1522Configure.
1523
1524If the libs variable looks correct, you might have the
1525L<"nm extraction"> problem discussed above.
1526
1527If you stil have missing routines or undefined symbols, you probably
1528need to add some library or other, or you need to undefine some feature
1529that Configure thought was there but is defective or incomplete. If
1530you used a hint file, see if it has any relevant advice. You can also
1531look through through config.h for likely suspects.
8e07c86e 1532
1ec51d55 1533=item toke.c
8e07c86e 1534
1ec51d55 1535Some compilers will not compile or optimize the larger files (such as
1536toke.c) without some extra switches to use larger jump offsets or
1537allocate larger internal tables. You can customize the switches for
1538each file in cflags. It's okay to insert rules for specific files into
1539makefile since a default rule only takes effect in the absence of a
8e07c86e 1540specific rule.
1541
7f678428 1542=item Missing dbmclose
8e07c86e 1543
c3edaffb 1544SCO prior to 3.2.4 may be missing dbmclose(). An upgrade to 3.2.4
1545that includes libdbm.nfs (which includes dbmclose()) may be available.
8e07c86e 1546
f3d9a6ba 1547=item Note (probably harmless): No library found for -lsomething
7f678428 1548
1549If you see such a message during the building of an extension, but
1550the extension passes its tests anyway (see L<"make test"> below),
1551then don't worry about the warning message. The extension
1552Makefile.PL goes looking for various libraries needed on various
aa689395 1553systems; few systems will need all the possible libraries listed.
74b7c41f 1554Most users will see warnings for the ones they don't have. The
1555phrase 'probably harmless' is intended to reassure you that nothing
1556unusual is happening, and the build process is continuing.
7f678428 1557
1558On the other hand, if you are building GDBM_File and you get the
1559message
1560
f3d9a6ba 1561 Note (probably harmless): No library found for -lgdbm
7f678428 1562
1563then it's likely you're going to run into trouble somewhere along
1564the line, since it's hard to see how you can use the GDBM_File
1565extension without the -lgdbm library.
1566
1567It is true that, in principle, Configure could have figured all of
1568this out, but Configure and the extension building process are not
1569quite that tightly coordinated.
1570
aa689395 1571=item sh: ar: not found
1572
1573This is a message from your shell telling you that the command 'ar'
1574was not found. You need to check your PATH environment variable to
1575make sure that it includes the directory with the 'ar' command. This
1ec51d55 1576is a common problem on Solaris, where 'ar' is in the /usr/ccs/bin
aa689395 1577directory.
1578
1579=item db-recno failure on tests 51, 53 and 55
1580
1581Old versions of the DB library (including the DB library which comes
1582with FreeBSD 2.1) had broken handling of recno databases with modified
1583bval settings. Upgrade your DB library or OS.
1584
6087ac44 1585=item Bad arg length for semctl, is XX, should be ZZZ
1586
11906ba0 1587If you get this error message from the ext/IPC/SysV/t/sem test, your System
6087ac44 1588V IPC may be broken. The XX typically is 20, and that is what ZZZ
1589also should be. Consider upgrading your OS, or reconfiguring your OS
1590to include the System V semaphores.
1591
11906ba0 1592=item ext/IPC/SysV/t/sem........semget: No space left on device
220f3621 1593
1594Either your account or the whole system has run out of semaphores. Or
1595both. Either list the semaphores with "ipcs" and remove the unneeded
1596ones (which ones these are depends on your system and applications)
1597with "ipcrm -s SEMAPHORE_ID_HERE" or configure more semaphores to your
1598system.
1599
d6baa268 1600=item GNU binutils
1601
1602If you mix GNU binutils (nm, ld, ar) with equivalent vendor-supplied
1603tools you may be in for some trouble. For example creating archives
1604with an old GNU 'ar' and then using a new current vendor-supplied 'ld'
1605may lead into linking problems. Either recompile your GNU binutils
1606under your current operating system release, or modify your PATH not
1607to include the GNU utils before running Configure, or specify the
1608vendor-supplied utilities explicitly to Configure, for example by
1609Configure -Dar=/bin/ar.
1610
16dc217a 1611=item THIS PACKAGE SEEMS TO BE INCOMPLETE
1612
1613The F<Configure> program has not been able to find all the files which
1614make up the complete Perl distribution. You may have a damaged source
1615archive file (in which case you may also have seen messages such as
1616C<gzip: stdin: unexpected end of file> and C<tar: Unexpected EOF on
1617archive file>), or you may have obtained a structurally-sound but
1618incomplete archive. In either case, try downloading again from the
1619official site named at the start of this document. If you do find
1620that any site is carrying a corrupted or incomplete source code
1621archive, please report it to the site's maintainer.
1622
16dc217a 1623=item invalid token: ##
1624
ce80d64e 1625You are using a non-ANSI-compliant C compiler. To compile Perl, you
1626need to use a compiler that supports ANSI C. If there is a README
1627file for your system, it may have further details on your compiler
1628options.
16dc217a 1629
1ec51d55 1630=item Miscellaneous
8e07c86e 1631
7df75831 1632Some additional things that have been reported:
8e07c86e 1633
1634Genix may need to use libc rather than libc_s, or #undef VARARGS.
1635
1636NCR Tower 32 (OS 2.01.01) may need -W2,-Sl,2000 and #undef MKDIR.
1637
9ede5bc8 1638UTS may need one or more of -K or -g, and undef LSTAT.
8e07c86e 1639
11906ba0 1640FreeBSD can fail the ext/IPC/SysV/t/sem.t test if SysV IPC has not been
5cda700b 1641configured in the kernel. Perl tries to detect this, though, and
ce80d64e 1642you will get a message telling you what to do.
6087ac44 1643
6c8d78fb 1644Building Perl on a system that has also BIND (headers and libraries)
1645installed may run into troubles because BIND installs its own netdb.h
1646and socket.h, which may not agree with the operating system's ideas of
1647the same files. Similarly, including -lbind may conflict with libc's
1648view of the world. You may have to tweak -Dlocincpth and -Dloclibpth
1649to avoid the BIND.
1650
8e07c86e 1651=back
1652
58a21a9b 1653=head2 Cross-compilation
1654
e7a3c61b 1655Perl can be cross-compiled. It is just not trivial, cross-compilation
1656rarely is. Perl is routinely cross-compiled for many platforms (as of
1657June 2005 at least PocketPC aka WinCE, Open Zaurus, EPOC, Symbian, and
1658the IBM OS/400). These platforms are known as the B<target> platforms,
1659while the systems where the compilation takes place are the B<host>
1660platforms.
1661
1662What makes the situation difficult is that first of all,
1663cross-compilation environments vary significantly in how they are set
1664up and used, and secondly because the primary way of configuring Perl
1665(using the rather large Unix-tool-dependent Configure script) is not
1666awfully well suited for cross-compilation. However, starting from
1667version 5.8.0, the Configure script also knows one way of supporting
1668cross-compilation support, please keep reading.
1669
1670See the following files for more information about compiling Perl for
1671the particular platforms:
1672
1673=over 4
1674
1675=item WinCE/PocketPC
1676
75472953 1677README.ce
e7a3c61b 1678
1679=item Open Zaurus
1680
1681Cross/README
1682
1683=item EPOC
1684
1685README.epoc
1686
1687=item Symbian
1688
1689README.symbian
1690
1691=item OS/400
1692
1693README.os400
1694
1695=back
1696
1697Packaging and transferring either the core Perl modules or CPAN
1698modules to the target platform is also left up to the each
1699cross-compilation environment. Often the cross-compilation target
1700platforms are somewhat limited in diskspace: see the section
1701L<Minimizing the Perl installation> to learn more of the minimal set
1702of files required for a functional Perl installation.
1703
1704For some cross-compilation environments the Configure option
1705C<-Dinstallprefix=...> might be handy, see L<Changing the installation
1706directory>.
1707
1708About the cross-compilation support of Configure: what is known to
1709work is running Configure in a cross-compilation environment and
1710building the miniperl executable. What is known not to work is
1711building the perl executable because that would require building
1712extensions: Dynaloader statically and File::Glob dynamically, for
1713extensions one needs MakeMaker and MakeMaker is not yet
1714cross-compilation aware, and neither is the main Makefile.
1715
1716The cross-compilation setup of Configure has successfully been used in
1717at least two Linux cross-compilation environments. The setups were
1718both such that the host system was Intel Linux with a gcc built for
1719cross-compiling into ARM Linux, and there was a SSH connection to the
1720target system.
1721
1722To run Configure in cross-compilation mode the basic switch that
1723has to be used is C<-Dusecrosscompile>.
58a21a9b 1724
1725 sh ./Configure -des -Dusecrosscompile -D...
1726
1727This will make the cpp symbol USE_CROSS_COMPILE and the %Config
b0f06652 1728symbol C<usecrosscompile> available, and C<xconfig.h> will be used
1729for cross-compilation.
58a21a9b 1730
1731During the Configure and build, certain helper scripts will be created
1732into the Cross/ subdirectory. The scripts are used to execute a
1733cross-compiled executable, and to transfer files to and from the
1734target host. The execution scripts are named F<run-*> and the
1735transfer scripts F<to-*> and F<from-*>. The part after the dash is
1736the method to use for remote execution and transfer: by default the
1737methods are B<ssh> and B<scp>, thus making the scripts F<run-ssh>,
1738F<to-scp>, and F<from-scp>.
1739
1740To configure the scripts for a target host and a directory (in which
1741the execution will happen and which is to and from where the transfer
1742happens), supply Configure with
1743
1744 -Dtargethost=so.me.ho.st -Dtargetdir=/tar/get/dir
1745
1746The targethost is what e.g. ssh will use as the hostname, the targetdir
93bc48fa 1747must exist (the scripts won't create it), the targetdir defaults to /tmp.
1748You can also specify a username to use for ssh/rsh logins
58a21a9b 1749
1750 -Dtargetuser=luser
1751
1752but in case you don't, "root" will be used.
1753
93bc48fa 1754Because this is a cross-compilation effort, you will also need to specify
1755which target environment and which compilation environment to use.
1756This includes the compiler, the header files, and the libraries.
1757In the below we use the usual settings for the iPAQ cross-compilation
1758environment:
58a21a9b 1759
1760 -Dtargetarch=arm-linux
1761 -Dcc=arm-linux-gcc
1762 -Dusrinc=/skiff/local/arm-linux/include
1763 -Dincpth=/skiff/local/arm-linux/include
1764 -Dlibpth=/skiff/local/arm-linux/lib
1765
1766If the name of the C<cc> has the usual GNU C semantics for cross
1767compilers, that is, CPU-OS-gcc, the names of the C<ar>, C<nm>, and
1768C<ranlib> will also be automatically chosen to be CPU-OS-ar and so on.
93bc48fa 1769(The C<ld> requires more thought and will be chosen later by Configure
1770as appropriate.) Also, in this case the incpth, libpth, and usrinc
1771will be guessed by Configure (unless explicitly set to something else,
1772in which case Configure's guesses with be appended).
58a21a9b 1773
1774In addition to the default execution/transfer methods you can also
1775choose B<rsh> for execution, and B<rcp> or B<cp> for transfer,
1776for example:
1777
1778 -Dtargetrun=rsh -Dtargetto=rcp -Dtargetfrom=cp
1779
1780Putting it all together:
1781
1782 sh ./Configure -des -Dusecrosscompile \
93bc48fa 1783 -Dtargethost=so.me.ho.st \
1784 -Dtargetdir=/tar/get/dir \
58a21a9b 1785 -Dtargetuser=root \
1786 -Dtargetarch=arm-linux \
1787 -Dcc=arm-linux-gcc \
1788 -Dusrinc=/skiff/local/arm-linux/include \
1789 -Dincpth=/skiff/local/arm-linux/include \
1790 -Dlibpth=/skiff/local/arm-linux/lib \
1791 -D...
1792
e7a3c61b 1793or if you are happy with the defaults:
93bc48fa 1794
1795 sh ./Configure -des -Dusecrosscompile \
1796 -Dtargethost=so.me.ho.st \
1797 -Dcc=arm-linux-gcc \
1798 -D...
1799
e7a3c61b 1800Another example where the cross-compiler has been installed under
1801F</usr/local/arm/2.95.5>:
1802
1803 sh ./Configure -des -Dusecrosscompile \
1804 -Dtargethost=so.me.ho.st \
1805 -Dcc=/usr/local/arm/2.95.5/bin/arm-linux-gcc \
1806 -Dincpth=/usr/local/arm/2.95.5/include \
1807 -Dusrinc=/usr/local/arm/2.95.5/include \
1808 -Dlibpth=/usr/local/arm/2.95.5/lib
1809
8e07c86e 1810=head1 make test
1811
d6baa268 1812This will run the regression tests on the perl you just made. If
1813'make test' doesn't say "All tests successful" then something went
1814wrong. See the file t/README in the t subdirectory.
84902520 1815
84902520 1816Note that you can't run the tests in background if this disables
fb73857a 1817opening of /dev/tty. You can use 'make test-notty' in that case but
1818a few tty tests will be skipped.
c3edaffb 1819
c4f23d77 1820=head2 What if make test doesn't work?
1821
1ec51d55 1822If make test bombs out, just cd to the t directory and run ./TEST
1823by hand to see if it makes any difference. If individual tests
c3edaffb 1824bomb, you can run them by hand, e.g.,
8e07c86e 1825
785aa5e3 1826 cd t ; ./perl -MTestInit op/groups.t
8e07c86e 1827
aa689395 1828Another way to get more detailed information about failed tests and
1ec51d55 1829individual subtests is to cd to the t directory and run
aa689395 1830
785aa5e3 1831 cd t ; ./perl harness <list of tests>
aa689395 1832
fb73857a 1833(this assumes that most basic tests succeed, since harness uses
785aa5e3 1834complicated constructs). If no list of tests is provided, harness
1835will run all tests.
10c7e831 1836
fb73857a 1837You should also read the individual tests to see if there are any helpful
10c7e831 1838comments that apply to your system. You may also need to setup your
1839shared library path if you get errors like:
1840
1841 /sbin/loader: Fatal Error: cannot map libperl.so
1842
1843See L</"Building a shared Perl library"> earlier in this document.
c3edaffb 1844
c4f23d77 1845=over 4
1846
1847=item locale
1848
1ec51d55 1849Note: One possible reason for errors is that some external programs
c07a80fd 1850may be broken due to the combination of your environment and the way
785aa5e3 1851'make test' exercises them. For example, this may happen if you have
1ec51d55 1852one or more of these environment variables set: LC_ALL LC_CTYPE
1853LC_COLLATE LANG. In some versions of UNIX, the non-English locales
e57fd563 1854are known to cause programs to exhibit mysterious errors.
1855
1856If you have any of the above environment variables set, please try
aa689395 1857
1858 setenv LC_ALL C
1859
1860(for C shell) or
1861
1862 LC_ALL=C;export LC_ALL
1863
1ec51d55 1864for Bourne or Korn shell) from the command line and then retry
1865make test. If the tests then succeed, you may have a broken program that
aa689395 1866is confusing the testing. Please run the troublesome test by hand as
e57fd563 1867shown above and see whether you can locate the program. Look for
1ec51d55 1868things like: exec, `backquoted command`, system, open("|...") or
1869open("...|"). All these mean that Perl is trying to run some
e57fd563 1870external program.
eed2e782 1871
0740bb5b 1872=item Timing problems
1873
c29923ff 1874Several tests in the test suite check timing functions, such as
1875sleep(), and see if they return in a reasonable amount of time.
9341413f 1876If your system is quite busy and doesn't respond quickly enough,
1877these tests might fail. If possible, try running the tests again
1878with the system under a lighter load. These timing-sensitive
1879and load-sensitive tests include F<t/op/alarm.t>,
3831a787 1880F<ext/Time-HiRes/t/HiRes.t>, F<ext/threads-shared/t/waithires.t>,
1881F<ext/threads-shared/t/stress.t>, F<lib/Benchmark.t>,
9341413f 1882F<lib/Memoize/t/expmod_t.t>, and F<lib/Memoize/t/speed.t>.
0740bb5b 1883
f89caa8d 1884You might also experience some failures in F<t/op/stat.t> if you build
1885perl on an NFS filesystem, if the remote clock and the system clock are
1886different.
1887
c4f23d77 1888=item Out of memory
1889
1890On some systems, particularly those with smaller amounts of RAM, some
1891of the tests in t/op/pat.t may fail with an "Out of memory" message.
7970f296 1892For example, on my SparcStation IPC with 12 MB of RAM, in perl5.5.670,
1893test 85 will fail if run under either t/TEST or t/harness.
c4f23d77 1894
1895Try stopping other jobs on the system and then running the test by itself:
1896
785aa5e3 1897 cd t; ./perl -MTestInit op/pat.t
c4f23d77 1898
1899to see if you have any better luck. If your perl still fails this
1900test, it does not necessarily mean you have a broken perl. This test
1901tries to exercise the regular expression subsystem quite thoroughly,
1902and may well be far more demanding than your normal usage.
1903
a55bb48b 1904=item libgcc_s.so.1: cannot open shared object file
1905
1906This message has been reported on gcc-3.2.3 and earlier installed with
1907a non-standard prefix. Setting the LD_LIBRARY_PATH environment variable
1908(or equivalent) to include gcc's lib/ directory with the libgcc_s.so.1
1909shared library should fix the problem.
1910
4f76e5ba 1911=item Failures from lib/File/Temp/t/security saying "system possibly insecure"
1912
1913First, such warnings are not necessarily serious or indicative of a
1914real security threat. That being said, they bear investigating.
1915
1916Note that each of the tests is run twice. The first time is in the
1917directory returned by File::Spec->tmpdir() (often /tmp on Unix
1918systems), and the second time in the directory from which the test was
1919run (usually the 't' directory, if the test was run as part of 'make
1920test').
1921
1922The tests may fail for the following reasons:
1923
1924(1) If the directory the tests are being run in is owned by somebody
1925other than the user running the tests, or by root (uid 0).
1926
1927This failure can happen if the Perl source code distribution is
1928unpacked in such a way that the user ids in the distribution package
1929are used as-is. Some tar programs do this.
1930
1931(2) If the directory the tests are being run in is writable by group or
1932by others, and there is no sticky bit set for the directory. (With
1933UNIX/POSIX semantics, write access to a directory means the right to
1934add or remove files in that directory. The 'sticky bit' is a feature
1935used in some UNIXes to give extra protection to files: if the bit is
1936set for a directory, no one but the owner (or root) can remove that
1937file even if the permissions would otherwise allow file removal by
1938others.)
1939
1940This failure may or may not be a real problem: it depends on the
1941permissions policy used on this particular system. This failure can
1942also happen if the system either doesn't support the sticky bit (this
1943is the case with many non-UNIX platforms: in principle File::Temp
1944should know about these platforms and skip the tests), or if the system
1945supports the sticky bit but for some reason or reasons it is not being
1946used. This is, for example, the case with HP-UX: as of HP-UX release
194711.00, the sticky bit is very much supported, but HP-UX doesn't use it
1948on its /tmp directory as shipped. Also, as with the permissions, some
1949local policy might dictate that the stickiness is not used.
781948c1 1950
b2b23189 1951(3) If the system supports the POSIX 'chown giveaway' feature and if
1952any of the parent directories of the temporary file back to the root
1953directory are 'unsafe', using the definitions given above in (1) and
4f76e5ba 1954(2). For Unix systems, this is usually not an issue if you are
1955building on a local disk. See the documentation for the File::Temp
1956module for more information about 'chown giveaway'.
781948c1 1957
1958See the documentation for the File::Temp module for more information
4f76e5ba 1959about the various security aspects of temporary files.
781948c1 1960
c4f23d77 1961=back
1962
5ee651a9 1963The core distribution can now run its regression tests in parallel on
1964Unix-like platforms. Instead of running C<make test>, set C<TEST_JOBS> in
1965your environment to the number of tests to run in parallel, and run
1966C<make test_harness>. On a Bourne-like shell, this can be done as
1967
1968 TEST_JOBS=3 make test_harness # Run 3 tests in parallel
1969
1970An environment variable is used, rather than parallel make itself, because
1971L<TAP::Harness> needs to be able to schedule individual non-conflicting test
1972scripts itself, and there is no standard interface to C<make> utilities to
1973interact with their job schedulers.
1974
8e07c86e 1975=head1 make install
1976
1977This will put perl into the public directory you specified to
1ec51d55 1978Configure; by default this is /usr/local/bin. It will also try
8e07c86e 1979to put the man pages in a reasonable place. It will not nroff the man
aa689395 1980pages, however. You may need to be root to run B<make install>. If you
ce80d64e 1981are not root, you must still have permission to install into the directories
1982in question and you should ignore any messages about chown not working.
1983
1984If "make install" just says "`install' is up to date" or something
1985similar, you may be on a case-insensitive filesystems such as Mac's HFS+,
1986and you should say "make install-all". (This confusion is brought to you
1987by the Perl distribution having a file called INSTALL.)
8e07c86e 1988
dd64f1c3 1989=head2 Installing perl under different names
1990
1991If you want to install perl under a name other than "perl" (for example,
1992when installing perl with special features enabled, such as debugging),
1993indicate the alternate name on the "make install" line, such as:
1994
1995 make install PERLNAME=myperl
1996
beb13193 1997You can separately change the base used for versioned names (like
be8498a1 1998"perl5.8.9") by setting PERLNAME_VERBASE, like
beb13193 1999
2000 make install PERLNAME=perl5 PERLNAME_VERBASE=perl
2001
5cda700b 2002This can be useful if you have to install perl as "perl5" (e.g. to
2003avoid conflicts with an ancient version in /usr/bin supplied by your vendor).
be8498a1 2004Without this the versioned binary would be called "perl55.8.8".
beb13193 2005
ce80d64e 2006=head2 Installing perl under a different directory
2007
2008You can install perl under a different destination directory by using
2009the DESTDIR variable during C<make install>, with a command like
2010
2011 make install DESTDIR=/tmp/perl5
2012
2013DESTDIR is automatically prepended to all the installation paths. See
7df75831 2014the example in L<"DESTDIR"> above.
ce80d64e 2015
dd64f1c3 2016=head2 Installed files
2017
8e07c86e 2018If you want to see exactly what will happen without installing
2019anything, you can run
4633a7c4 2020
8e07c86e 2021 ./perl installperl -n
2022 ./perl installman -n
2023
1ec51d55 2024make install will install the following:
8e07c86e 2025
d56c5707 2026 binaries
2027
8e07c86e 2028 perl,
be8498a1 2029 perl5.n.n where 5.n.n is the current release number. This
8e07c86e 2030 will be a link to perl.
2031 suidperl,
be8498a1 2032 sperl5.n.n If you requested setuid emulation.
8e07c86e 2033 a2p awk-to-perl translator
d56c5707 2034
2035 scripts
2036
73d6d1b0 2037 cppstdin This is used by the deprecated switch perl -P, if
2038 your cc -E can't read from stdin.
8e07c86e 2039 c2ph, pstruct Scripts for handling C structures in header files.
73d6d1b0 2040 config_data Manage Module::Build-like module configuration
2041 corelist Shows versions of modules that come with different
2042 versions of perl
2043 cpan The CPAN shell
2044 cpan2dist The CPANPLUS distribution creator
2045 cpanp The CPANPLUS shell
2046 cpanp-run-perl An helper for cpanp
f5b5f377 2047 dprofpp Perl code profiler post-processor
73d6d1b0 2048 enc2xs Encoding module generator
8e07c86e 2049 find2perl find-to-perl translator
aa689395 2050 h2ph Extract constants and simple macros from C headers
8e07c86e 2051 h2xs Converts C .h header files to Perl extensions.
73d6d1b0 2052 instmodsh A shell to examine installed modules.
2053 libnetcfg Configure libnet.
24b3df7f 2054 perlbug Tool to report bugs in Perl.
8e07c86e 2055 perldoc Tool to read perl's pod documentation.
73d6d1b0 2056 perlivp Perl Installation Verification Procedure
2057 piconv A Perl implementation of the encoding conversion
2058 utility iconv
aa689395 2059 pl2pm Convert Perl 4 .pl files to Perl 5 .pm modules
8e07c86e 2060 pod2html, Converters from perl's pod documentation format
aa689395 2061 pod2latex, to other useful formats.
d56c5707 2062 pod2man,
2063 pod2text,
d56c5707 2064 pod2usage
73d6d1b0 2065 podchecker POD syntax checker
2066 podselect Prints sections of POD documentation
2067 prove A command-line tool for running tests
2068 psed A Perl implementation of sed
2069 ptar A Perl implementation of tar
2070 ptardiff A diff for tar archives
2071 s2p sed-to-perl translator
2072 shasum A tool to print or check SHA checksums
aa689395 2073 splain Describe Perl warnings and errors
73d6d1b0 2074 xsubpp Compiler to convert Perl XS code into C code
8e07c86e 2075
d56c5707 2076 library files
2077
2078 in $privlib and $archlib specified to
8e07c86e 2079 Configure, usually under /usr/local/lib/perl5/.
d56c5707 2080
2081 documentation
2082
d6baa268 2083 man pages in $man1dir, usually /usr/local/man/man1.
2084 module man
2085 pages in $man3dir, usually /usr/local/man/man3.
8e07c86e 2086 pod/*.pod in $privlib/pod/.
2087
33cceb07 2088installperl will also create the directories listed above
d6baa268 2089in L<"Installation Directories">.
4633a7c4 2090
d56c5707 2091Perl's *.h header files and the libperl library are also installed
d6baa268 2092under $archlib so that any user may later build new modules, run the
56c6f531 2093optional Perl compiler, or embed the perl interpreter into another
2094program even if the Perl source is no longer available.
8e07c86e 2095
33cceb07 2096=head2 Installing only version-specific parts
2097
d56c5707 2098Sometimes you only want to install the version-specific parts of the perl
2099installation. For example, you may wish to install a newer version of
33cceb07 2100perl alongside an already installed production version without
d56c5707 2101disabling installation of new modules for the production version.
2102To only install the version-specific parts of the perl installation, run
2103
2104 Configure -Dversiononly
2105
2106or answer 'y' to the appropriate Configure prompt. Alternatively,
2107you can just manually run
2108
2109 ./perl installperl -v
2110
2111and skip installman altogether.
33cceb07 2112
d56c5707 2113See also L<"Maintaining completely separate versions"> for another
2114approach.
2115
f4ce0e6d 2116=head1 cd /usr/include; h2ph *.h sys/*.h
2117
2118Some perl scripts need to be able to obtain information from the
2119system header files. This command will convert the most commonly used
2120header files in /usr/include into files that can be easily interpreted
2121by perl. These files will be placed in the architecture-dependent
2122library ($archlib) directory you specified to Configure.
2123
2124Note: Due to differences in the C and perl languages, the conversion
2125of the header files is not perfect. You will probably have to
2126hand-edit some of the converted files to get them to parse correctly.
2127For example, h2ph breaks spectacularly on type casting and certain
2128structures.
2129
2130=head1 installhtml --help
2131
2132Some sites may wish to make perl documentation available in HTML
2133format. The installhtml utility can be used to convert pod
2134documentation into linked HTML files and install them.
2135
2136Currently, the supplied ./installhtml script does not make use of the
2137html Configure variables. This should be fixed in a future release.
2138
2139The following command-line is an example of one used to convert
2140perl documentation:
2141
2142 ./installhtml \
2143 --podroot=. \
2144 --podpath=lib:ext:pod:vms \
2145 --recurse \
2146 --htmldir=/perl/nmanual \
2147 --htmlroot=/perl/nmanual \
2148 --splithead=pod/perlipc \
2149 --splititem=pod/perlfunc \
2150 --libpods=perlfunc:perlguts:perlvar:perlrun:perlop \
2151 --verbose
2152
2153See the documentation in installhtml for more details. It can take
2154many minutes to execute a large installation and you should expect to
2155see warnings like "no title", "unexpected directive" and "cannot
2156resolve" as the files are processed. We are aware of these problems
2157(and would welcome patches for them).
2158
2159You may find it helpful to run installhtml twice. That should reduce
2160the number of "cannot resolve" warnings.
2161
2162=head1 cd pod && make tex && (process the latex files)
2163
2164Some sites may also wish to make the documentation in the pod/ directory
2165available in TeX format. Type
2166
2167 (cd pod && make tex && <process the latex files>)
2168
2169=head1 Starting all over again
2170
2171If you wish to re-build perl from the same build directory, you should
2172clean it out with the command
2173
2174 make distclean
2175
2176or
2177
2178 make realclean
2179
2180The only difference between the two is that make distclean also removes
2181your old config.sh and Policy.sh files.
2182
2183If you are upgrading from a previous version of perl, or if you
2184change systems or compilers or make other significant changes, or if
2185you are experiencing difficulties building perl, you should not re-use
2186your old config.sh.
2187
2188If your reason to reuse your old config.sh is to save your particular
2189installation choices, then you can probably achieve the same effect by
2190using the Policy.sh file. See the section on L<"Site-wide Policy
2191settings"> above.
2192
ff52061e 2193=head1 Reporting Problems
2194
2195Wherever possible please use the perlbug tool supplied with this Perl
2196to report problems, as it automatically includes summary configuration
2197information about your perl, which may help us track down problems far
2198more quickly. But first you should read the advice in this file,
2199carefully re-read the error message and check the relevant manual pages
2200on your system, as these may help you find an immediate solution. If
2201you are not sure whether what you are seeing is a bug, you can send a
2202message describing the problem to the comp.lang.perl.misc newsgroup to
2203get advice.
2204
2205The perlbug tool is installed along with perl, so after you have
2206completed C<make install> it should be possible to run it with plain
2207C<perlbug>. If the install fails, or you want to report problems with
2208C<make test> without installing perl, then you can use C<make nok> to
2209run perlbug to report the problem, or run it by hand from this source
2210directory with C<./perl -Ilib utils/perlbug>
2211
2212If the build fails too early to run perlbug uninstalled, then please
2213B<run> the C<./myconfig> shell script, and mail its output along with
2214an accurate description of your problem to perlbug@perl.org
2215
2216If Configure itself fails, and does not generate a config.sh file
2217(needed to run C<./myconfig>), then please mail perlbug@perl.org the
2218description of how Configure fails along with details of your system
2219- for example the output from running C<uname -a>
2220
2221Please try to make your message brief but clear. Brief, clear bug
2222reports tend to get answered more quickly. Please don't worry if your
2223written English is not great - what matters is how well you describe
2224the important technical details of the problem you have encountered,
2225not whether your grammar and spelling is flawless.
2226
2227Trim out unnecessary information. Do not include large files (such as
2228config.sh or a complete Configure or make log) unless absolutely
2229necessary. Do not include a complete transcript of your build
2230session. Just include the failing commands, the relevant error
2231messages, and whatever preceding commands are necessary to give the
2232appropriate context. Plain text should usually be sufficient--fancy
2233attachments or encodings may actually reduce the number of people who
2234read your message. Your message will get relayed to over 400
2235subscribers around the world so please try to keep it brief but clear.
2236
5acb7768 2237If the bug you are reporting has security implications, which make it
2238inappropriate to send to a publicly archived mailing list, then please send
2239it to perl5-security-report@perl.org. This points to a closed subscription
2240unarchived mailing list, which includes all the core committers, who be able
2241to help assess the impact of issues, figure out a resolution, and help
2242co-ordinate the release of patches to mitigate or fix the problem across all
2243platforms on which Perl is supported. Please only use this address for security
2244issues in the Perl core, not for modules independently distributed on CPAN.
2245
ff52061e 2246If you are unsure what makes a good bug report please read "How to
2247report Bugs Effectively" by Simon Tatham:
2248http://www.chiark.greenend.org.uk/~sgtatham/bugs.html
2249
7df75831 2250=head1 Coexistence with earlier versions of perl 5
4633a7c4 2251
fdd3cf50 2252Perl 5.10 is not binary compatible with earlier versions of Perl.
cc65bb49 2253In other words, you will have to recompile your XS modules.
14eee2f1 2254
693762b4 2255In general, you can usually safely upgrade from one version of Perl (e.g.
33cceb07 22565.X.Y) to another similar minor version (e.g. 5.X.(Y+1))) without
2257re-compiling all of your extensions. You can also safely leave the old
2258version around in case the new version causes you problems for some reason.
693762b4 2259
be8498a1 2260Usually, most extensions will probably not need to be recompiled to be
2261used with a newer version of Perl. Here is how it is supposed to work.
ce80d64e 2262(These examples assume you accept all the Configure defaults.)
693762b4 2263
33cceb07 2264Suppose you already have version 5.8.7 installed. The directories
2265searched by 5.8.7 are typically like:
d6baa268 2266
33cceb07 2267 /usr/local/lib/perl5/5.8.7/$archname
2268 /usr/local/lib/perl5/5.8.7
2269 /usr/local/lib/perl5/site_perl/5.8.7/$archname
2270 /usr/local/lib/perl5/site_perl/5.8.7
d6baa268 2271
33cceb07 2272Now, suppose you install version 5.8.8. The directories
2273searched by version 5.8.8 will be:
d6baa268 2274
33cceb07 2275 /usr/local/lib/perl5/5.8.8/$archname
2276 /usr/local/lib/perl5/5.8.8
2277 /usr/local/lib/perl5/site_perl/5.8.8/$archname
2278 /usr/local/lib/perl5/site_perl/5.8.8
d6baa268 2279
33cceb07 2280 /usr/local/lib/perl5/site_perl/5.8.7/$archname
2281 /usr/local/lib/perl5/site_perl/5.8.7
c42e3e15 2282 /usr/local/lib/perl5/site_perl/
bfb7748a 2283
c42e3e15 2284Notice the last three entries -- Perl understands the default structure
d6baa268 2285of the $sitelib directories and will look back in older, compatible
33cceb07 2286directories. This way, modules installed under 5.8.7 will continue
2287to be usable by 5.8.7 but will also accessible to 5.8.8. Further,
d6baa268 2288suppose that you upgrade a module to one which requires features
33cceb07 2289present only in 5.8.8. That new module will get installed into
2290/usr/local/lib/perl5/site_perl/5.8.8 and will be available to 5.8.8,
2291but will not interfere with the 5.8.7 version.
bfb7748a 2292
c42e3e15 2293The last entry, /usr/local/lib/perl5/site_perl/, is there so that
fe23a901 22945.6.0 and above will look for 5.004-era pure perl modules.
d6baa268 2295
33cceb07 2296Lastly, suppose you now install 5.10.0, which is not binary compatible
2297with 5.8.x. The directories searched by 5.10.0 (if you don't change the
fe23a901 2298Configure defaults) will be:
2299
33cceb07 2300 /usr/local/lib/perl5/5.10.0/$archname
2301 /usr/local/lib/perl5/5.10.0
2302 /usr/local/lib/perl5/site_perl/5.10.0/$archname
2303 /usr/local/lib/perl5/site_perl/5.10.0
d6baa268 2304
33cceb07 2305 /usr/local/lib/perl5/site_perl/5.8.8
d6baa268 2306
33cceb07 2307 /usr/local/lib/perl5/site_perl/5.8.7
fe23a901 2308
d6baa268 2309 /usr/local/lib/perl5/site_perl/
bfb7748a 2310
cc65bb49 2311Note that the earlier $archname entries are now gone, but pure perl
2312modules from earlier versions will still be found.
2313
0a08c020 2314This way, you can choose to share compatible extensions, but also upgrade
2315to a newer version of an extension that may be incompatible with earlier
2316versions, without breaking the earlier versions' installations.
693762b4 2317
2318=head2 Maintaining completely separate versions
4633a7c4 2319
1ec51d55 2320Many users prefer to keep all versions of perl in completely
d6baa268 2321separate directories. This guarantees that an update to one version
0a08c020 2322won't interfere with another version. (The defaults guarantee this for
2323libraries after 5.6.0, but not for executables. TODO?) One convenient
2324way to do this is by using a separate prefix for each version, such as
d52d4e46 2325
33cceb07 2326 sh Configure -Dprefix=/opt/perl5.10.0
d52d4e46 2327
33cceb07 2328and adding /opt/perl5.10.0/bin to the shell PATH variable. Such users
d52d4e46 2329may also wish to add a symbolic link /usr/local/bin/perl so that
2330scripts can still start with #!/usr/local/bin/perl.
2331
693762b4 2332Others might share a common directory for maintenance sub-versions
33cceb07 2333(e.g. 5.10 for all 5.10.x versions), but change directory with
693762b4 2334each major version.
2335
6877a1cf 2336If you are installing a development subversion, you probably ought to
2337seriously consider using a separate directory, since development
2338subversions may not have all the compatibility wrinkles ironed out
2339yet.
2340
dd3196cd 2341=head2 Upgrading from 5.8.x or earlier
693762b4 2342
dd3196cd 2343B<Perl 5.10.0 is binary incompatible with Perl 5.8.x and any earlier
2344Perl release.> Perl modules having binary parts
e655887d 2345(meaning that a C compiler is used) will have to be recompiled to be
dd3196cd 2346used with 5.10.0. If you find you do need to rebuild an extension with
23475.10.0, you may safely do so without disturbing the older
7df75831 2348installations. (See L<"Coexistence with earlier versions of perl 5">
e655887d 2349above.)
c42e3e15 2350
2351See your installed copy of the perllocal.pod file for a (possibly
2352incomplete) list of locally installed modules. Note that you want
cc65bb49 2353perllocal.pod, not perllocale.pod, for installed module information.
693762b4 2354
8ebf57cf 2355=head1 Minimizing the Perl installation
2356
2357The following section is meant for people worrying about squeezing the
2358Perl installation into minimal systems (for example when installing
2359operating systems, or in really small filesystems).
2360
c8214fdf 2361Leaving out as many extensions as possible is an obvious way:
5cda700b 2362Encode, with its big conversion tables, consumes a lot of
2363space. On the other hand, you cannot throw away everything. The
2364Fcntl module is pretty essential. If you need to do network
c8214fdf 2365programming, you'll appreciate the Socket module, and so forth: it all
2366depends on what do you need to do.
2367
8ebf57cf 2368In the following we offer two different slimmed down installation
2369recipes. They are informative, not normative: the choice of files
2370depends on what you need.
2371
2372Firstly, the bare minimum to run this script
2373
2374 use strict;
2375 use warnings;
2376 foreach my $f (</*>) {
2377 print("$f\n");
2378 }
2379
bfe08c74 2380in Linux is as follows (under $Config{prefix}):
8ebf57cf 2381
2382 ./bin/perl
bfe08c74 2383 ./lib/perl5/5.9.3/strict.pm
2384 ./lib/perl5/5.9.3/warnings.pm
2385 ./lib/perl5/5.9.3/i686-linux/File/Glob.pm
2386 ./lib/perl5/5.9.3/i686-linux/XSLoader.pm
2387 ./lib/perl5/5.9.3/i686-linux/auto/File/Glob/Glob.so
8ebf57cf 2388
2389Secondly, Debian perl-base package contains the following files,
bfe08c74 2390size about 1.9MB in its i386 version:
8ebf57cf 2391
bfe08c74 2392 /usr/bin/perl
2393 /usr/bin/perl5.8.4
2394 /usr/lib/perl/5.8
2395 /usr/lib/perl/5.8.4/B.pm
2396 /usr/lib/perl/5.8.4/B/Deparse.pm
2397 /usr/lib/perl/5.8.4/Config.pm
2398 /usr/lib/perl/5.8.4/Cwd.pm
2399 /usr/lib/perl/5.8.4/Data/Dumper.pm
2400 /usr/lib/perl/5.8.4/DynaLoader.pm
2401 /usr/lib/perl/5.8.4/Errno.pm
2402 /usr/lib/perl/5.8.4/Fcntl.pm
2403 /usr/lib/perl/5.8.4/File/Glob.pm
2404 /usr/lib/perl/5.8.4/IO.pm
2405 /usr/lib/perl/5.8.4/IO/File.pm
2406 /usr/lib/perl/5.8.4/IO/Handle.pm
2407 /usr/lib/perl/5.8.4/IO/Pipe.pm
2408 /usr/lib/perl/5.8.4/IO/Seekable.pm
2409 /usr/lib/perl/5.8.4/IO/Select.pm
2410 /usr/lib/perl/5.8.4/IO/Socket.pm
2411 /usr/lib/perl/5.8.4/POSIX.pm
2412 /usr/lib/perl/5.8.4/Socket.pm
2413 /usr/lib/perl/5.8.4/XSLoader.pm
2414 /usr/lib/perl/5.8.4/auto/Cwd/Cwd.bs
2415 /usr/lib/perl/5.8.4/auto/Cwd/Cwd.so
2416 /usr/lib/perl/5.8.4/auto/Data/Dumper/Dumper.bs
2417 /usr/lib/perl/5.8.4/auto/Data/Dumper/Dumper.so
2418 /usr/lib/perl/5.8.4/auto/DynaLoader/DynaLoader.a
2419 /usr/lib/perl/5.8.4/auto/DynaLoader/autosplit.ix
2420 /usr/lib/perl/5.8.4/auto/DynaLoader/dl_expandspec.al
2421 /usr/lib/perl/5.8.4/auto/DynaLoader/dl_find_symbol_anywhere.al
2422 /usr/lib/perl/5.8.4/auto/DynaLoader/dl_findfile.al
2423 /usr/lib/perl/5.8.4/auto/DynaLoader/extralibs.ld
2424 /usr/lib/perl/5.8.4/auto/Fcntl/Fcntl.bs
2425 /usr/lib/perl/5.8.4/auto/Fcntl/Fcntl.so
2426 /usr/lib/perl/5.8.4/auto/File/Glob/Glob.bs
2427 /usr/lib/perl/5.8.4/auto/File/Glob/Glob.so
2428 /usr/lib/perl/5.8.4/auto/IO/IO.bs
2429 /usr/lib/perl/5.8.4/auto/IO/IO.so
2430 /usr/lib/perl/5.8.4/auto/POSIX/POSIX.bs
2431 /usr/lib/perl/5.8.4/auto/POSIX/POSIX.so
2432 /usr/lib/perl/5.8.4/auto/POSIX/autosplit.ix
2433 /usr/lib/perl/5.8.4/auto/POSIX/load_imports.al
2434 /usr/lib/perl/5.8.4/auto/Socket/Socket.bs
2435 /usr/lib/perl/5.8.4/auto/Socket/Socket.so
2436 /usr/lib/perl/5.8.4/lib.pm
2437 /usr/lib/perl/5.8.4/re.pm
2438 /usr/share/doc/perl-base
8ebf57cf 2439 /usr/share/doc/perl/AUTHORS.gz
bfe08c74 2440 /usr/share/doc/perl/Documentation
2441 /usr/share/doc/perl/README.Debian.gz
8ebf57cf 2442 /usr/share/doc/perl/changelog.Debian.gz
bfe08c74 2443 /usr/share/doc/perl/copyright
8ebf57cf 2444 /usr/share/man/man1/perl.1.gz
bfe08c74 2445 /usr/share/perl/5.8
2446 /usr/share/perl/5.8.4/AutoLoader.pm
2447 /usr/share/perl/5.8.4/Carp.pm
2448 /usr/share/perl/5.8.4/Carp/Heavy.pm
2449 /usr/share/perl/5.8.4/Exporter.pm
2450 /usr/share/perl/5.8.4/Exporter/Heavy.pm
2451 /usr/share/perl/5.8.4/File/Spec.pm
2452 /usr/share/perl/5.8.4/File/Spec/Unix.pm
2453 /usr/share/perl/5.8.4/FileHandle.pm
2454 /usr/share/perl/5.8.4/Getopt/Long.pm
2455 /usr/share/perl/5.8.4/IO/Socket/INET.pm
2456 /usr/share/perl/5.8.4/IO/Socket/UNIX.pm
2457 /usr/share/perl/5.8.4/IPC/Open2.pm
2458 /usr/share/perl/5.8.4/IPC/Open3.pm
2459 /usr/share/perl/5.8.4/List/Util.pm
2460 /usr/share/perl/5.8.4/Scalar/Util.pm
2461 /usr/share/perl/5.8.4/SelectSaver.pm
2462 /usr/share/perl/5.8.4/Symbol.pm
2463 /usr/share/perl/5.8.4/Text/ParseWords.pm
2464 /usr/share/perl/5.8.4/Text/Tabs.pm
2465 /usr/share/perl/5.8.4/Text/Wrap.pm
2466 /usr/share/perl/5.8.4/attributes.pm
2467 /usr/share/perl/5.8.4/base.pm
2468 /usr/share/perl/5.8.4/bytes.pm
2469 /usr/share/perl/5.8.4/bytes_heavy.pl
2470 /usr/share/perl/5.8.4/constant.pm
2471 /usr/share/perl/5.8.4/fields.pm
2472 /usr/share/perl/5.8.4/integer.pm
2473 /usr/share/perl/5.8.4/locale.pm
2474 /usr/share/perl/5.8.4/overload.pm
2475 /usr/share/perl/5.8.4/strict.pm
2476 /usr/share/perl/5.8.4/utf8.pm
2477 /usr/share/perl/5.8.4/utf8_heavy.pl
2478 /usr/share/perl/5.8.4/vars.pm
2479 /usr/share/perl/5.8.4/warnings.pm
2480 /usr/share/perl/5.8.4/warnings/register.pm
8ebf57cf 2481
e7a3c61b 2482A nice trick to find out the minimal set of Perl library files you will
2483need to run a Perl program is
2484
a0a8d9d3 2485 perl -e 'do "prog.pl"; END { print "$_\n" for sort keys %INC }'
e7a3c61b 2486
2487(this will not find libraries required in runtime, unfortunately, but
2488it's a minimal set) and if you want to find out all the files you can
2489use something like the below
2490
2491 strace perl -le 'do "x.pl"' 2>&1 | perl -nle '/^open\(\"(.+?)"/ && print $1'
2492
2493(The 'strace' is Linux-specific, other similar utilities include 'truss'
2494and 'ktrace'.)
2495
c19ccd8c 2496=head2 C<-DNO_MATHOMS>
2497
2498If you configure perl with C<-Accflags=-DNO_MATHOMS>, the functions from
2499F<mathoms.c> will not be compiled in. Those functions are no longer used
2500by perl itself; for source compatibility reasons, though, they weren't
2501completely removed.
2502
8e07c86e 2503=head1 DOCUMENTATION
2504
bfb7748a 2505Read the manual entries before running perl. The main documentation
2506is in the pod/ subdirectory and should have been installed during the
8e07c86e 2507build process. Type B<man perl> to get started. Alternatively, you
bfb7748a 2508can type B<perldoc perl> to use the supplied perldoc script. This is
2509sometimes useful for finding things in the library modules.
8e07c86e 2510
2511=head1 AUTHOR
2512
bfb7748a 2513Original author: Andy Dougherty doughera@lafayette.edu , borrowing very
2514heavily from the original README by Larry Wall, with lots of helpful
2515feedback and additions from the perl5-porters@perl.org folks.
fb73857a 2516
f5b3b617 2517If you have problems, corrections, or questions, please see
2518L<"Reporting Problems"> above.
2519
2520=head1 REDISTRIBUTION
2521
2522This document is part of the Perl package and may be distributed under
d6baa268 2523the same terms as perl itself, with the following additional request:
f5b3b617 2524If you are distributing a modified version of perl (perhaps as part of
d6baa268 2525a larger package) please B<do> modify these installation instructions
2526and the contact information to match your distribution.