compatibility fix: magic non-propagation in foreach implicit localization
[p5sagit/p5-mst-13.2.git] / README.win32
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68dc0745 1If you read this file _as_is_, just ignore the funny characters you
2see. It is written in the POD format (see pod/perlpod.pod) which is
3specially designed to be readable as is.
4
5=head1 NAME
6
5aabfad6 7perlwin32 - Perl under Win32
68dc0745 8
9=head1 SYNOPSIS
10
7bac28a0 11These are instructions for building Perl under Windows NT (versions
9036c72f 123.51 or 4.0). Currently, this port is reported to build
26618a56 13under Windows95 using the 4DOS shell--the default shell that infests
14Windows95 will not work (see below). Note this caveat is only about
3e3baf6d 15B<building> perl. Once built, you should be able to B<use> it on
16either Win32 platform (modulo the problems arising from the inferior
17command shell).
68dc0745 18
19=head1 DESCRIPTION
20
3fe9a6f1 21Before you start, you should glance through the README file
68dc0745 22found in the top-level directory where the Perl distribution
23was extracted. Make sure you read and understand the terms under
24which this software is being distributed.
25
f7c603cb 26Also make sure you read L<BUGS AND CAVEATS> below for the
68dc0745 27known limitations of this port.
28
29The INSTALL file in the perl top-level has much information that is
30only relevant to people building Perl on Unix-like systems. In
31particular, you can safely ignore any information that talks about
32"Configure".
33
7bac28a0 34You may also want to look at two other options for building
35a perl that will work on Windows NT: the README.cygwin32 and
3e3baf6d 36README.os2 files, which each give a different set of rules to build
37a Perl that will work on Win32 platforms. Those two methods will
7bac28a0 38probably enable you to build a more Unix-compatible perl, but you
39will also need to download and use various other build-time and
40run-time support software described in those files.
68dc0745 41
42This set of instructions is meant to describe a so-called "native"
43port of Perl to Win32 platforms. The resulting Perl requires no
44additional software to run (other than what came with your operating
9036c72f 45system). Currently, this port is capable of using one of the
46following compilers:
47
48 Borland C++ version 5.02 or later
49 Microsoft Visual C++ version 4.2 or later
9a40db4d 50 Mingw32 with EGCS versions 1.0.2, 1.1
9036c72f 51 Mingw32 with GCC version 2.8.1
52
a29d2910 53The last two of these are high quality freeware compilers. Support
54for them is still experimental.
5aabfad6 55
56This port currently supports MakeMaker (the set of modules that
57is used to build extensions to perl). Therefore, you should be
58able to build and install most extensions found in the CPAN sites.
c90c0ff4 59See L<Usage Hints> below for general hints about this.
68dc0745 60
61=head2 Setting Up
62
63=over 4
64
3e3baf6d 65=item Command Shell
68dc0745 66
26618a56 67Use the default "cmd" shell that comes with NT. Some versions of the
68popular 4DOS/NT shell have incompatibilities that may cause you trouble.
69If the build fails under that shell, try building again with the cmd
70shell. The Makefile also has known incompatibilites with the "command.com"
71shell that comes with Windows95, so building under Windows95 should
72be considered "unsupported". However, there have been reports of successful
b8957cf1 73build attempts using 4DOS/NT version 6.01 under Windows95, using dmake, but
26618a56 74your mileage may vary.
75
76The surest way to build it is on WindowsNT, using the cmd shell.
68dc0745 77
a8deba26 78Make sure the path to the build directory does not contain spaces. The
79build usually works in this circumstance, but some tests will fail.
80
3e3baf6d 81=item Borland C++
82
83If you are using the Borland compiler, you will need dmake, a freely
84available make that has very nice macro features and parallelability.
85(The make that Borland supplies is seriously crippled, and will not
26618a56 86work for MakeMaker builds.)
87
88A port of dmake for win32 platforms is available from:
3e3baf6d 89
26618a56 90 http://www-personal.umich.edu/~gsar/dmake-4.1-win32.zip
91
92Fetch and install dmake somewhere on your path (follow the instructions
93in the README.NOW file).
3e3baf6d 94
95=item Microsoft Visual C++
68dc0745 96
3e3baf6d 97The NMAKE that comes with Visual C++ will suffice for building.
9036c72f 98You will need to run the VCVARS32.BAT file usually found somewhere
99like C:\MSDEV4.2\BIN. This will set your build environment.
68dc0745 100
26618a56 101You can also use dmake to build using Visual C++, provided:
102you set OSRELEASE to "microsft" (or whatever the directory name
103under which the Visual C dmake configuration lives) in your environment,
104and edit win32/config.vc to change "make=nmake" into "make=dmake". The
105latter step is only essential if you want to use dmake as your default
106make for building extensions using MakeMaker.
3e3baf6d 107
9036c72f 108=item Mingw32 with EGCS or GCC
109
80252599 110ECGS binaries can be downloaded from:
9036c72f 111
112 ftp://ftp.xraylith.wisc.edu/pub/khan/gnu-win32/mingw32/
68dc0745 113
9036c72f 114GCC-2.8.1 binaries are available from:
68dc0745 115
9036c72f 116 http://agnes.dida.physik.uni-essen.de/~janjaap/mingw32/
68dc0745 117
9036c72f 118You only need either one of those, not both. Both bundles come with
119Mingw32 libraries and headers. While both of them work to build perl,
120the EGCS binaries are currently favored by the maintainers, since they
121come with more up-to-date Mingw32 libraries.
122
123Make sure you install the binaries as indicated in the web sites
124above. You will need to set up a few environment variables (usually
125run from a batch file).
68dc0745 126
ee4d903c 127You also need dmake. See L</"Borland C++"> above on how to get it.
128
68dc0745 129=back
130
137443ea 131=head2 Building
68dc0745 132
133=over 4
134
135=item *
136
68dc0745 137Make sure you are in the "win32" subdirectory under the perl toplevel.
137443ea 138This directory contains a "Makefile" that will work with
9036c72f 139versions of NMAKE that come with Visual C++, and a dmake "makefile.mk"
140that will work for all supported compilers. The defaults in the dmake
141makefile are setup to build using the Borland compiler.
68dc0745 142
143=item *
144
9036c72f 145Edit the makefile.mk (or Makefile, if using nmake) and change the values
146of INST_DRV and INST_TOP. You can also enable various build
26618a56 147flags.
148
9036c72f 149Beginning with version 5.005, there is experimental support for building
150a perl interpreter that supports the Perl Object abstraction (courtesy
151ActiveState Tool Corp.) PERL_OBJECT uses C++, and the binaries are
152therefore incompatible with the regular C build. However, the
153PERL_OBJECT build does provide something called the C-API, for linking
80252599 154it with extensions that won't compile under PERL_OBJECT. Using the C_API
155is typically requested through:
156
157 perl Makefile.PL CAPI=TRUE
158
159PERL_OBJECT requires VC++ 5.0 (Service Pack 3 recommended) or later. It
9cde0e7f 160is not yet supported under GCC or EGCS. WARNING: Binaries built with
161PERL_OBJECT enabled are B<not> compatible with binaries built without.
162Perl installs PERL_OBJECT binaries under a distinct architecture name,
163so they B<can> coexist, though.
9036c72f 164
165Beginning with version 5.005, there is experimental support for building
166a perl interpreter that is capable of native threading. Binaries built
167with thread support enabled are also incompatible with the vanilla C
9cde0e7f 168build. WARNING: Binaries built with threads enabled are B<not> compatible
169with binaries built without. Perl installs threads enabled binaries under
170a distinct architecture name, so they B<can> coexist, though.
9036c72f 171
172At the present time, you cannot enable both threading and PERL_OBJECT.
173You can get only one of them in a Perl interpreter.
174
26618a56 175If you have either the source or a library that contains des_fcrypt(),
176enable the appropriate option in the makefile. des_fcrypt() is not
177bundled with the distribution due to US Government restrictions
178on the export of cryptographic software. Nevertheless, this routine
179is part of the "libdes" library (written by Ed Young) which is widely
180available worldwide, usually along with SSLeay (for example:
181"ftp://fractal.mta.ca/pub/crypto/SSLeay/DES/"). Set CRYPT_SRC to the
182name of the file that implements des_fcrypt(). Alternatively, if
183you have built a library that contains des_fcrypt(), you can set
2d77217b 184CRYPT_LIB to point to the library name. The location above contains
185many versions of the "libdes" library, all with slightly different
186implementations of des_fcrypt(). Older versions have a single,
187self-contained file (fcrypt.c) that implements crypt(), so they may be
188easier to use. A patch against the fcrypt.c found in libdes-3.06 is
189in des_fcrypt.patch.
26618a56 190
191Perl will also build without des_fcrypt(), but the crypt() builtin will
192fail at run time.
c90c0ff4 193
3e3baf6d 194You will also have to make sure CCHOME points to wherever you installed
80252599 195your compiler.
a8deba26 196
197The default value for CCHOME in the makefiles for Visual C++
ee4d903c 198may not be correct for some versions. Make sure the default exists
199and is valid.
c90c0ff4 200
9036c72f 201Other options are explained in the makefiles. Be sure to read the
202instructions carefully.
203
68dc0745 204=item *
205
9036c72f 206Type "dmake" (or "nmake" if you are using that make).
68dc0745 207
137443ea 208This should build everything. Specifically, it will create perl.exe,
9036c72f 209perl.dll (or perlcore.dll), and perlglob.exe at the perl toplevel, and
210various other extension dll's under the lib\auto directory. If the build
211fails for any reason, make sure you have done the previous steps correctly.
68dc0745 212
156a3eb7 213The build process may produce "harmless" compiler warnings (more or
214less copiously, depending on how picky your compiler gets). The
215maintainers are aware of these warnings, thankyouverymuch. :)
216
3e3baf6d 217When building using Visual C++, a perl95.exe will also get built. This
218executable is only needed on Windows95, and should be used instead of
219perl.exe, and then only if you want sockets to work properly on Windows95.
220This is necessitated by a bug in the Microsoft C Runtime that cannot be
26618a56 221worked around in the "normal" perl.exe. perl95.exe gets built with its
222own private copy of the C Runtime that is not accessible to extensions
223(which see the DLL version of the CRT). Be aware, therefore, that this
224perl95.exe will have esoteric problems with extensions like perl/Tk that
225themselves use the C Runtime heavily, or want to free() pointers
226malloc()-ed by perl.
3e3baf6d 227
af06e6b3 228You can avoid the perl95.exe problems completely if you either enable
229USE_PERLCRT with Visual C++, or use Borland C++ for building perl. In
230those cases, perl95.exe is not needed and will not be built.
3e3baf6d 231
68dc0745 232=back
233
234=head2 Testing
235
9036c72f 236Type "dmake test" (or "nmake test"). This will run most of the tests from
3e3baf6d 237the testsuite (many tests will be skipped, and but no test should fail).
68dc0745 238
8b88ae92 239If some tests do fail, it may be because you are using a different command
a8deba26 240shell than the native "cmd.exe", or because you are building from a path
241that contains spaces. So don't do that.
68dc0745 242
a8deba26 243If you're using the Borland compiler, you may see a failure in op/taint.t
3e3baf6d 244arising from the inability to find the Borland Runtime DLLs on the system
245default path. You will need to copy the DLLs reported by the messages
246from where Borland chose to install it, into the Windows system directory
247(usually somewhere like C:\WINNT\SYSTEM32), and rerun the test.
248
9036c72f 249The Visual C runtime apparently has a bug that causes posix.t to fail
9a40db4d 250test#2. This usually happens only if you extracted the files in text
251mode. Enable the USE_PERLCRT option in the Makefile to fix this bug.
9036c72f 252
3e3baf6d 253Please report any other failures as described under L<BUGS AND CAVEATS>.
68dc0745 254
137443ea 255=head2 Installation
256
9036c72f 257Type "dmake install" (or "nmake install"). This will put the newly
26618a56 258built perl and the libraries under whatever C<INST_TOP> points to in the
259Makefile. It will also install the pod documentation under
9036c72f 260C<$INST_TOP\$VERSION\lib\pod> and HTML versions of the same under
261C<$INST_TOP\$VERSION\lib\pod\html>. To use the Perl you just installed,
262you will need to add two components to your PATH environment variable,
263C<$INST_TOP\$VERSION\bin>, and C<$INST_TOP\$VERSION\bin\$ARCHNAME>.
264For example:
265
80252599 266 set PATH c:\perl\5.005\bin;c:\perl\5.005\bin\MSWin32-x86;%PATH%
9036c72f 267
137443ea 268
7bac28a0 269=head2 Usage Hints
270
271=over 4
272
273=item Environment Variables
274
275The installation paths that you set during the build get compiled
276into perl, so you don't have to do anything additional to start
277using that perl (except add its location to your PATH variable).
278
279If you put extensions in unusual places, you can set PERL5LIB
280to a list of paths separated by semicolons where you want perl
281to look for libraries. Look for descriptions of other environment
26618a56 282variables you can set in L<perlrun>.
283
284You can also control the shell that perl uses to run system() and
285backtick commands via PERL5SHELL. See L<perlrun>.
7bac28a0 286
9a40db4d 287Perl does not depend on the registry, but it can look up certain default
288values if you choose to put them there. Perl attempts to read entries from
289C<HKEY_CURRENT_USER\Software\Perl> and C<HKEY_LOCAL_MACHINE\Software\Perl>.
290Entries in the former override entries in the latter. One or more of the
291following entries (of type REG_SZ or REG_EXPAND_SZ) may be set:
292
293 lib-$] version-specific path to add to @INC
294 lib path to add to @INC
295 sitelib-$] version-specific path to add to @INC
296 sitelib path to add to @INC
297 PERL* fallback for all %ENV lookups that begin with "PERL"
298
299Note the C<$]> in the above is not literal. Substitute whatever version
300of perl you want to honor that entry, e.g. C<5.00502>. Paths must be
301separated with semicolons, as usual on win32.
7bac28a0 302
3e3baf6d 303=item File Globbing
304
305By default, perl spawns an external program to do file globbing.
306The install process installs both a perlglob.exe and a perlglob.bat
307that perl can use for this purpose. Note that with the default
308installation, perlglob.exe will be found by the system before
309perlglob.bat.
310
311perlglob.exe relies on the argv expansion done by the C Runtime of
312the particular compiler you used, and therefore behaves very
313differently depending on the Runtime used to build it. To preserve
dfb634a9 314compatiblity, perlglob.bat (a perl script that can be used portably)
315is installed. Besides being portable, perlglob.bat also offers
316enhanced globbing functionality.
3e3baf6d 317
318If you want perl to use perlglob.bat instead of perlglob.exe, just
319delete perlglob.exe from the install location (or move it somewhere
dfb634a9 320perl cannot find). Using File::DosGlob.pm (which implements the core
321functionality of perlglob.bat) to override the internal CORE::glob()
322works about 10 times faster than spawing perlglob.exe, and you should
323take this approach when writing new modules. See File::DosGlob for
324details.
3e3baf6d 325
7bac28a0 326=item Using perl from the command line
327
328If you are accustomed to using perl from various command-line
329shells found in UNIX environments, you will be less than pleased
330with what Windows NT offers by way of a command shell.
331
332The crucial thing to understand about the "cmd" shell (which is
333the default on Windows NT) is that it does not do any wildcard
334expansions of command-line arguments (so wildcards need not be
335quoted). It also provides only rudimentary quoting. The only
336(useful) quote character is the double quote ("). It can be used to
337protect spaces in arguments and other special characters. The
338Windows NT documentation has almost no description of how the
339quoting rules are implemented, but here are some general observations
340based on experiments: The shell breaks arguments at spaces and
341passes them to programs in argc/argv. Doublequotes can be used
342to prevent arguments with spaces in them from being split up.
343You can put a double quote in an argument by escaping it with
344a backslash and enclosing the whole argument within double quotes.
345The backslash and the pair of double quotes surrounding the
346argument will be stripped by the shell.
347
348The file redirection characters "<", ">", and "|" cannot be quoted
349by double quotes (there are probably more such). Single quotes
350will protect those three file redirection characters, but the
351single quotes don't get stripped by the shell (just to make this
352type of quoting completely useless). The caret "^" has also
353been observed to behave as a quoting character (and doesn't get
354stripped by the shell also).
355
356Here are some examples of usage of the "cmd" shell:
357
358This prints two doublequotes:
359
360 perl -e "print '\"\"' "
361
362This does the same:
363
364 perl -e "print \"\\\"\\\"\" "
365
366This prints "bar" and writes "foo" to the file "blurch":
367
368 perl -e "print 'foo'; print STDERR 'bar'" > blurch
369
370This prints "foo" ("bar" disappears into nowhereland):
371
372 perl -e "print 'foo'; print STDERR 'bar'" 2> nul
373
374This prints "bar" and writes "foo" into the file "blurch":
375
376 perl -e "print 'foo'; print STDERR 'bar'" 1> blurch
377
7bac28a0 378This pipes "foo" to the "less" pager and prints "bar" on the console:
379
380 perl -e "print 'foo'; print STDERR 'bar'" | less
381
382This pipes "foo\nbar\n" to the less pager:
383
7bac28a0 384 perl -le "print 'foo'; print STDERR 'bar'" 2>&1 | less
385
386This pipes "foo" to the pager and writes "bar" in the file "blurch":
387
388 perl -e "print 'foo'; print STDERR 'bar'" 2> blurch | less
389
390
84902520 391Discovering the usefulness of the "command.com" shell on Windows95
7bac28a0 392is left as an exercise to the reader :)
393
394=item Building Extensions
395
396The Comprehensive Perl Archive Network (CPAN) offers a wealth
397of extensions, some of which require a C compiler to build.
398Look in http://www.perl.com/ for more information on CPAN.
399
400Most extensions (whether they require a C compiler or not) can
401be built, tested and installed with the standard mantra:
402
403 perl Makefile.PL
3e3baf6d 404 $MAKE
405 $MAKE test
406 $MAKE install
7bac28a0 407
ee4d903c 408where $MAKE is whatever 'make' program you have configured perl to
409use. Use "perl -V:make" to find out what this is. Some extensions
410may not provide a testsuite (so "$MAKE test" may not do anything, or
411fail), but most serious ones do.
412
413It is important that you use a supported 'make' program, and
414ensure Config.pm knows about it. If you don't have nmake, you can
415either get dmake from the location mentioned earlier, or get an
416old version of nmake reportedly available from:
417
418 ftp://ftp.microsoft.com/Softlib/MSLFILES/nmake15.exe
419
420Another option is to use the make written in Perl, available from
421CPAN:
422
423 http://www.perl.com/CPAN/authors/id/NI-S/Make-0.03.tar.gz
424
425Note that MakeMaker actually emits makefiles with different syntax
426depending on what 'make' it thinks you are using. Therefore, it is
427important that one of the following values appears in Config.pm:
428
429 make='nmake' # MakeMaker emits nmake syntax
430 make='dmake' # MakeMaker emits dmake syntax
431 any other value # MakeMaker emits generic make syntax
432 (e.g GNU make, or Perl make)
433
434If the value doesn't match the 'make' program you want to use,
435edit Config.pm to fix it.
7bac28a0 436
3e3baf6d 437If a module implements XSUBs, you will need one of the supported
438C compilers. You must make sure you have set up the environment for
439the compiler for command-line compilation.
7bac28a0 440
3e3baf6d 441If a module does not build for some reason, look carefully for
7bac28a0 442why it failed, and report problems to the module author. If
443it looks like the extension building support is at fault, report
444that with full details of how the build failed using the perlbug
445utility.
446
9cde0e7f 447=item Command-line Wildcard Expansion
448
449The default command shells on DOS descendant operating systems (such
450as they are) usually do not expand wildcard arguments supplied to
451programs. They consider it the application's job to handle that.
452This is commonly achieved by linking the application (in our case,
453perl) with startup code that the C runtime libraries usually provide.
454However, doing that results in incompatible perl versions (since the
455behavior of the argv expansion code differs depending on the
456compiler, and it is even buggy on some compilers). Besides, it may
457be a source of frustration if you use such a perl binary with an
458alternate shell that *does* expand wildcards.
459
460Instead, the following solution works rather well. The nice things
461about it: 1) you can start using it right away 2) it is more powerful,
462because it will do the right thing with a pattern like */*/*.c
4633) you can decide whether you do/don't want to use it 4) you can
464extend the method to add any customizations (or even entirely
465different kinds of wildcard expansion).
466
467 C:\> copy con c:\perl\lib\Wild.pm
468 # Wild.pm - emulate shell @ARGV expansion on shells that don't
469 use File::DosGlob;
470 @ARGV = map {
471 my @g = File::DosGlob::glob($_) if /[*?]/;
472 @g ? @g : $_;
473 } @ARGV;
474 1;
475 ^Z
476 C:\> set PERL5OPT=-MWild
477 C:\> perl -le "for (@ARGV) { print }" */*/perl*.c
478 p4view/perl/perl.c
479 p4view/perl/perlio.c
480 p4view/perl/perly.c
481 perl5.005/win32/perlglob.c
482 perl5.005/win32/perllib.c
483 perl5.005/win32/perlglob.c
484 perl5.005/win32/perllib.c
485 perl5.005/win32/perlglob.c
486 perl5.005/win32/perllib.c
487
488Note there are two distinct steps there: 1) You'll have to create
489Wild.pm and put it in your perl lib directory. 2) You'll need to
490set the PERL5OPT environment variable. If you want argv expansion
491to be the default, just set PERL5OPT in your default startup
492environment.
493
494If you are using the Visual C compiler, you can get the C runtime's
495command line wildcard expansion built into perl binary. The resulting
496binary will always expand unquoted command lines, which may not be
497what you want if you use a shell that does that for you. The expansion
498done is also somewhat less powerful than the approach suggested above.
499
c90c0ff4 500=item Win32 Specific Extensions
501
502A number of extensions specific to the Win32 platform are available
503from CPAN. You may find that many of these extensions are meant to
504be used under the Activeware port of Perl, which used to be the only
505native port for the Win32 platform. Since the Activeware port does not
506have adequate support for Perl's extension building tools, these
507extensions typically do not support those tools either, and therefore
508cannot be built using the generic steps shown in the previous section.
509
510To ensure smooth transitioning of existing code that uses the
9036c72f 511ActiveState port, there is a bundle of Win32 extensions that contains
512all of the ActiveState extensions and most other Win32 extensions from
c90c0ff4 513CPAN in source form, along with many added bugfixes, and with MakeMaker
514support. This bundle is available at:
515
a8deba26 516 http://www.perl.com/CPAN/authors/id/GSAR/libwin32-0.14.zip
c90c0ff4 517
518See the README in that distribution for building and installation
519instructions. Look for later versions that may be available at the
520same location.
521
156a3eb7 522=item Running Perl Scripts
523
524Perl scripts on UNIX use the "#!" (a.k.a "shebang") line to
525indicate to the OS that it should execute the file using perl.
526Win32 has no comparable means to indicate arbitrary files are
527executables.
528
529Instead, all available methods to execute plain text files on
530Win32 rely on the file "extension". There are three methods
531to use this to execute perl scripts:
532
533=over 8
534
535=item 1
536
537There is a facility called "file extension associations" that will
538work in Windows NT 4.0. This can be manipulated via the two
539commands "assoc" and "ftype" that come standard with Windows NT
5404.0. Type "ftype /?" for a complete example of how to set this
541up for perl scripts (Say what? You thought Windows NT wasn't
542perl-ready? :).
543
544=item 2
545
546Since file associations don't work everywhere, and there are
547reportedly bugs with file associations where it does work, the
548old method of wrapping the perl script to make it look like a
549regular batch file to the OS, may be used. The install process
550makes available the "pl2bat.bat" script which can be used to wrap
551perl scripts into batch files. For example:
552
553 pl2bat foo.pl
554
555will create the file "FOO.BAT". Note "pl2bat" strips any
556.pl suffix and adds a .bat suffix to the generated file.
557
558If you use the 4DOS/NT or similar command shell, note that
559"pl2bat" uses the "%*" variable in the generated batch file to
560refer to all the command line arguments, so you may need to make
561sure that construct works in batch files. As of this writing,
5624DOS/NT users will need a "ParameterChar = *" statement in their
5634NT.INI file, or will need to execute "setdos /p*" in the 4DOS/NT
564startup file to enable this to work.
565
566=item 3
567
568Using "pl2bat" has a few problems: the file name gets changed,
569so scripts that rely on C<$0> to find what they must do may not
570run properly; running "pl2bat" replicates the contents of the
571original script, and so this process can be maintenance intensive
572if the originals get updated often. A different approach that
573avoids both problems is possible.
574
575A script called "runperl.bat" is available that can be copied
576to any filename (along with the .bat suffix). For example,
577if you call it "foo.bat", it will run the file "foo" when it is
578executed. Since you can run batch files on Win32 platforms simply
579by typing the name (without the extension), this effectively
580runs the file "foo", when you type either "foo" or "foo.bat".
581With this method, "foo.bat" can even be in a different location
582than the file "foo", as long as "foo" is available somewhere on
583the PATH. If your scripts are on a filesystem that allows symbolic
584links, you can even avoid copying "runperl.bat".
585
586Here's a diversion: copy "runperl.bat" to "runperl", and type
587"runperl". Explain the observed behavior, or lack thereof. :)
588Hint: .gnidnats llits er'uoy fi ,"lrepnur" eteled :tniH
589
590=back
591
7bac28a0 592=item Miscellaneous Things
593
594A full set of HTML documentation is installed, so you should be
595able to use it if you have a web browser installed on your
596system.
597
598C<perldoc> is also a useful tool for browsing information contained
599in the documentation, especially in conjunction with a pager
600like C<less> (recent versions of which have Win32 support). You may
601have to set the PAGER environment variable to use a specific pager.
602"perldoc -f foo" will print information about the perl operator
603"foo".
604
605If you find bugs in perl, you can run C<perlbug> to create a
606bug report (you may have to send it manually if C<perlbug> cannot
607find a mailer on your system).
608
609=back
610
68dc0745 611=head1 BUGS AND CAVEATS
612
f7c603cb 613An effort has been made to ensure that the DLLs produced by the two
614supported compilers are compatible with each other (despite the
615best efforts of the compiler vendors). Extension binaries produced
616by one compiler should also coexist with a perl binary built by
617a different compiler. In order to accomplish this, PERL.DLL provides
618a layer of runtime code that uses the C Runtime that perl was compiled
619with. Extensions which include "perl.h" will transparently access
620the functions in this layer, thereby ensuring that both perl and
621extensions use the same runtime functions.
68dc0745 622
8b88ae92 623If you have had prior exposure to Perl on Unix platforms, you will notice
624this port exhibits behavior different from what is documented. Most of the
7bac28a0 625differences fall under one of these categories. We do not consider
626any of them to be serious limitations (especially when compared to the
627limited nature of some of the Win32 OSes themselves :)
68dc0745 628
629=over 8
630
631=item *
632
633C<stat()> and C<lstat()> functions may not behave as documented. They
634may return values that bear no resemblance to those reported on Unix
7bac28a0 635platforms, and some fields (like the the one for inode) may be completely
636bogus.
68dc0745 637
638=item *
639
6890e559 640The following functions are currently unavailable: C<fork()>,
5aabfad6 641C<dump()>, C<chown()>, C<link()>, C<symlink()>, C<chroot()>,
26618a56 642C<setpgrp()> and related security functions, C<setpriority()>,
643C<getpriority()>, C<syscall()>, C<fcntl()>, C<getpw*()>,
2d7a9237 644C<msg*()>, C<shm*()>, C<sem*()>, C<alarm()>, C<socketpair()>,
645C<*netent()>, C<*protoent()>, C<*servent()>, C<*hostent()>,
646C<getnetby*()>.
26618a56 647This list is possibly incomplete.
6890e559 648
649=item *
650
68dc0745 651Various C<socket()> related calls are supported, but they may not
652behave as on Unix platforms.
653
654=item *
655
656The four-argument C<select()> call is only supported on sockets.
657
658=item *
659
f998180f 660The C<ioctl()> call is only supported on sockets (where it provides the
661functionality of ioctlsocket() in the Winsock API).
662
663=item *
664
2d7a9237 665Failure to spawn() a subprocess is indicated by setting $? to "255 << 8".
666C<$?> is set in a way compatible with Unix (i.e. the exitstatus of the
667subprocess is obtained by "$? >> 8", as described in the documentation).
68dc0745 668
669=item *
670
26618a56 671You can expect problems building modules available on CPAN if you
672build perl itself with -DUSE_THREADS. These problems should be resolved
673as we get closer to 5.005.
68dc0745 674
675=item *
676
677C<utime()>, C<times()> and process-related functions may not
678behave as described in the documentation, and some of the
679returned values or effects may be bogus.
680
681=item *
682
3e3baf6d 683Signal handling may not behave as on Unix platforms (where it
f7c603cb 684doesn't exactly "behave", either :). For instance, calling C<die()>
685or C<exit()> from signal handlers will cause an exception, since most
686implementations of C<signal()> on Win32 are severely crippled.
687Thus, signals may work only for simple things like setting a flag
688variable in the handler. Using signals under this port should
689currently be considered unsupported.
68dc0745 690
691=item *
692
1a159553 693C<kill()> is implemented, but doesn't have the semantics of
694C<raise()>, i.e. it doesn't send a signal to the identified process
695like it does on Unix platforms. Instead it immediately calls
696C<TerminateProcess(process,signal)>. Thus the signal argument is
697used to set the exit-status of the terminated process. This behavior
698may change in future.
699
700=item *
701
7bac28a0 702File globbing may not behave as on Unix platforms. In particular,
3e3baf6d 703if you don't use perlglob.bat for globbing, it will understand
704wildcards only in the filename component (and not in the pathname).
705In other words, something like "print <*/*.pl>" will not print all the
706perl scripts in all the subdirectories one level under the current one
707(like it does on UNIX platforms). perlglob.exe is also dependent on
708the particular implementation of wildcard expansion in the vendor
709libraries used to build it (which varies wildly at the present time).
710Using perlglob.bat (or File::DosGlob) avoids these limitations, but
711still only provides DOS semantics (read "warts") for globbing.
68dc0745 712
713=back
714
715Please send detailed descriptions of any problems and solutions that
716you may find to <F<perlbug@perl.com>>, along with the output produced
717by C<perl -V>.
718
719=head1 AUTHORS
720
721=over 4
722
3e3baf6d 723Gary Ng E<lt>71564.1743@CompuServe.COME<gt>
68dc0745 724
3e3baf6d 725Gurusamy Sarathy E<lt>gsar@umich.eduE<gt>
68dc0745 726
3e3baf6d 727Nick Ing-Simmons E<lt>nick@ni-s.u-net.comE<gt>
68dc0745 728
729=back
730
f7c603cb 731This document is maintained by Gurusamy Sarathy.
732
68dc0745 733=head1 SEE ALSO
734
735L<perl>
736
737=head1 HISTORY
738
739This port was originally contributed by Gary Ng around 5.003_24,
740and borrowed from the Hip Communications port that was available
741at the time.
742
743Nick Ing-Simmons and Gurusamy Sarathy have made numerous and
744sundry hacks since then.
745
3e3baf6d 746Borland support was added in 5.004_01 (Gurusamy Sarathy).
747
9a40db4d 748GCC/mingw32 support was added in 5.005 (Nick Ing-Simmons).
749
80252599 750Support for PERL_OBJECT was added in 5.005 (ActiveState Tool Corp).
751
752Last updated: 18 January 1999
68dc0745 753
754=cut
3e3baf6d 755