Maintainer catch from Rafael.
[p5sagit/p5-mst-13.2.git] / README.vms
CommitLineData
b4bc034f 1If you read this file _as_is_, just ignore the equal signs on the left.
2This file is written in the POD format (see [.POD]PERLPOD.POD;1) which is
3specially designed to be readable as is.
fb73857a 4
b4bc034f 5=head1 NAME
6
7README.vms - Configuring, building, testing, and installing perl on VMS
8
9=head1 SYNOPSIS
10
11To configure, build, test, and install perl on VMS:
12
13 @ Configure
14 mms
15 mms test
16 mms install
17
18mmk may be used in place of mms in the last three steps.
19
20=head1 DESCRIPTION
21
22=head2 Important safety tip
97abc6ad 23
3a385817 24The build and install procedures have changed significantly from the 5.004
b4bc034f 25releases! Make sure you read the "Configuring the Perl Build", "Building
26Perl", and "Installing Perl" sections of this document before you build or
e7948fac 27install. Also please note other changes in the current release by having
28a look at L<perldelta/VMS>.
97abc6ad 29
b4bc034f 30Also note that, as of Perl version 5.005 and later, an ANSI C compliant
31compiler is required to build Perl. VAX C is *not* ANSI compliant, as it
32died a natural death some time before the standard was set. Therefore
1bc81404 33VAX C will not compile Perl 5.005 or later. We are sorry about that.
3bf5f72b 34
e7948fac 35If you are stuck without Compaq (formerly DEC) C consider trying Gnu C
36instead, though there have been no recent reports of builds using Gnu C.
37There is minimal support for Compaq C++ but this support is not complete;
38if you get it working please write to the vmsperl list (for info see
39L</"Mailing Lists">).
3bf5f72b 40
b4bc034f 41
a83b6f46 42=head2 Introduction to Perl on VMS
fb73857a 43
44The VMS port of Perl is as functionally complete as any other Perl port
45(and as complete as the ports on some Unix systems). The Perl binaries
46provide all the Perl system calls that are either available under VMS or
b4bc034f 47reasonably emulated. There are some incompatibilities in process handling
48(e.g. the fork/exec model for creating subprocesses doesn't do what you
fb73857a 49might expect under Unix), mainly because VMS and Unix handle processes and
50sub-processes very differently.
51
b4bc034f 52There are still some unimplemented system functions, and of course we
fb73857a 53could use modules implementing useful VMS system services, so if you'd like
b4bc034f 54to lend a hand we'd love to have you. Join the Perl Porting Team Now!
fb73857a 55
56The current sources and build procedures have been tested on a VAX using
b4bc034f 57DEC C, and on an AXP using DEC C. If you run into problems with
1bc81404 58other compilers, please let us know. (Note: DEC C was renamed to Compaq C
59around version 6.2).
fb73857a 60
b4bc034f 61There are issues with various versions of DEC C, so if you're not running a
62relatively modern version, check the "DEC C issues" section later on in this
fb73857a 63document.
64
a83b6f46 65=head2 Other required software for Compiling Perl on VMS
b4bc034f 66
67In addition to VMS and DCL you will need two things:
fb73857a 68
b4bc034f 69=over 4
70
71=item 1 A C compiler.
72
1bc81404 73DEC (now Compaq) C or gcc for VMS (AXP or VAX).
b4bc034f 74
75=item 2 A make tool.
76
77DEC's MMS (v2.6 or later), or MadGoat's free MMS
78analog MMK (available from ftp.madgoat.com/madgoat) both work
79just fine. Gnu Make might work, but it's been so long since
80anyone's tested it that we're not sure. MMK is free though, so
81go ahead and use that.
82
83=back
84
a83b6f46 85=head2 Additional software that is optional for Perl on VMS
fb73857a 86
9f3f8d50 87You may also want to have on hand:
b4bc034f 88
89=over 4
90
91=item 1 GUNZIP/GZIP.EXE for VMS
92
93A de-compressor for *.gz and *.tgz files available from a number
58979ab1 94of web/ftp sites and is distributed on the OpenVMS Freeware CD-ROM
95from Compaq.
b4bc034f 96
9f3f8d50 97 http://www.fsf.org/order/ftp.html
adc5a9a5 98 http://www.openvms.compaq.com/freeware/
1bc81404 99 http://www.crinoid.com/utils/
b4bc034f 100
101=item 2 VMS TAR
102
103For reading and writing unix tape archives (*.tar files). Vmstar is also
58979ab1 104available from a number of web/ftp sites and is distributed on the OpenVMS
105Freeware CD-ROM from Compaq.
b4bc034f 106
9f3f8d50 107 ftp://ftp.lp.se/vms/
adc5a9a5 108 http://www.openvms.compaq.com/freeware/
b4bc034f 109
110=item 3 UNZIP.EXE for VMS
111
112A combination decompressor and archive reader/writer for *.zip files.
113Unzip is available from a number of web/ftp sites.
114
adc5a9a5 115 http://www.info-zip.org/UnZip.html
116 http://www.openvms.compaq.com/freeware/
58979ab1 117 ftp://ftp.openvms.compaq.com/
b4bc034f 118 ftp://ftp.madgoat.com/madgoat/
adc5a9a5 119 ftp://ftp.process.com/vms-freeware/
b4bc034f 120
121=item 4 MOST
122
123Most is an optional pager that is convenient to use with perldoc (unlike
124TYPE/PAGE, MOST can go forward and backwards in a document and supports
125regular expression searching). Most builds with the slang
126library on VMS. Most and slang are available from:
127
128 ftp://space.mit.edu/pub/davis/
adc5a9a5 129 ftp://ftp.process.com/vms-freeware/narnia/
b4bc034f 130
1bc81404 131=item 5 GNU PATCH and DIFFUTILS for VMS
132
133Patches to Perl are usually distributed as GNU unified or contextual diffs.
134Such patches are created by the GNU diff program (part of the diffutils
135distribution) and applied with GNU patch. VMS ports of these utilities are
136available here:
137
138 http://www.crinoid.com/utils/
adc5a9a5 139 http://www.openvms.compaq.com/freeware/
1bc81404 140
b4bc034f 141=back
142
9f3f8d50 143Please note that UNZIP and GUNZIP are not the same thing (they work with
b4bc034f 144different formats). Many of the useful files from CPAN (the Comprehensive
58979ab1 145Perl Archive Network) are in *.tar.gz or *.tgz format (this includes copies
146of the source code for perl as well as modules and scripts that you may
147wish to add later) hence you probably want to have GUNZIP.EXE and
148VMSTAR.EXE on your VMS machine.
fb73857a 149
b4bc034f 150If you want to include socket support, you'll need a TCP/IP stack and either
151DEC C, or socket libraries. See the "Socket Support (optional)" topic
152for more details.
fb73857a 153
b4bc034f 154=head1 Configuring the Perl build
fb73857a 155
97abc6ad 156To configure perl (a necessary first step), issue the command
fb73857a 157
b4bc034f 158 @ Configure
fb73857a 159
b4bc034f 160from the top of an unpacked perl source directory. You will be asked a
161series of questions, and the answers to them (along with the capabilities
162of your C compiler and network stack) will determine how perl is custom
163built for your machine.
fb73857a 164
b4bc034f 165If you have multiple C compilers installed, you'll have your choice of
166which one to use. Various older versions of DEC C had some caveats, so if
167you're using a version older than 5.2, check the "DEC C Issues" section.
fb73857a 168
b4bc034f 169If you have any symbols or logical names in your environment that may
170interfere with the build or regression testing of perl then configure.com
171will try to warn you about them. If a logical name is causing
7bb57f25 172you trouble but is in an LNM table that you do not have write access to
173then try defining your own to a harmless equivalence string in a table
174such that it is resolved before the other (e.g. if TMP is defined in the
b4bc034f 175SYSTEM table then try DEFINE TMP "NL:" or somesuch in your process table)
176otherwise simply deassign the dangerous logical names. The potentially
177troublesome logicals and symbols are:
7bb57f25 178
b3b333bf 179 COMP "LOGICAL"
180 EXT "LOGICAL"
181 FOO "LOGICAL"
182 LIB "LOGICAL"
183 LIST "LOGICAL"
184 MIME "LOGICAL"
185 POSIX "LOGICAL"
186 SYS "LOGICAL"
187 T "LOGICAL"
188 THREAD "LOGICAL"
189 THREADS "LOGICAL"
190 TIME "LOGICAL"
191 TMP "LOGICAL"
192 UNICODE "LOGICAL"
193 UTIL "LOGICAL"
194 TEST "SYMBOL"
fb73857a 195
97abc6ad 196As a handy shortcut, the command:
197
b4bc034f 198 @ Configure "-des"
199
200(note the quotation marks and case) will choose reasonable defaults
201automatically (it takes DEC C over Gnu C, DEC C sockets over SOCKETSHR
1bc81404 202sockets, and either over no sockets). Some options can be given
203explicitly on the command line; the following example specifies a
204non-default location for where Perl will be installed:
205
206 @ Configure "-d" "-Dprefix=dka100:[utils.perl5.]"
207
dab31494 208Note that the installation location would be by default where you unpacked
fe05d1a7 209the source with a "_ROOT." appended. For example if you unpacked the perl
dab31494 210source into:
211
212 DKA200:[PERL-5_10_2...]
213
adc5a9a5 214Then the PERL_SETUP.COM that gets written out by CONFIGURE.COM will
dab31494 215try to DEFINE your installation PERL_ROOT to be:
216
fe05d1a7 217 DKA200:[PERL-5_10_2_ROOT.]
dab31494 218
1bc81404 219More help with configure.com is available from:
b4bc034f 220
221 @ Configure "-h"
222
223See the "Changing compile-time options (optional)" section below to learn
224even more details about how to influence the outcome of the important
225configuration step. If you find yourself reconfiguring and rebuilding
226then be sure to also follow the advice in the "Cleaning up and starting
227fresh (optional)" and the checklist of items in the "CAVEATS" sections
228below.
229
a83b6f46 230=head2 Changing compile-time options (optional) for Perl on VMS
b4bc034f 231
232Most of the user definable features of Perl are enabled or disabled in
adc5a9a5 233configure.com, which processes the hints file config_h.SH. There is
234code in there to Do The Right Thing, but that may end up being the
235wrong thing for you. Make sure you understand what you are doing since
236inappropriate changes to configure.com or config_h.SH can render perl
237unbuildable; odds are that there's nothing in there you'll need to
238change.
b4bc034f 239
240The one exception is the various *DIR install locations. Changing those
241requires changes in genconfig.pl as well. Be really careful if you need to
242change these, as they can cause some fairly subtle problems.
243
a83b6f46 244=head2 Socket Support (optional) for Perl on VMS
b4bc034f 245
246Perl includes a number of functions for IP sockets, which are available if
247you choose to compile Perl with socket support. Since IP networking is an
248optional addition to VMS, there are several different IP stacks available.
249How well integrated they are into the system depends on the stack, your
250version of VMS, and the version of your C compiler.
251
252The most portable solution uses the SOCKETSHR library. In combination with
253either UCX or NetLib, this supports all the major TCP stacks (Multinet,
254Pathways, TCPWare, UCX, and CMU) on all versions of VMS Perl runs on, with
255all the compilers on both VAX and Alpha. The socket interface is also
256consistent across versions of VMS and C compilers. It has a problem with
257UDP sockets when used with Multinet, though, so you should be aware of
258that.
259
260The other solution available is to use the socket routines built into DEC
261C. Which routines are available depend on the version of VMS you're
262running, and require proper UCX emulation by your TCP/IP vendor.
263Relatively current versions of Multinet, TCPWare, Pathway, and UCX all
264provide the required libraries--check your manuals or release notes to see
265if your version is new enough.
266
267=head1 Building Perl
268
269The configuration script will print out, at the very end, the MMS or MMK
270command you need to compile perl. Issue it (exactly as printed) to start
271the build.
97abc6ad 272
b4bc034f 273Once you issue your MMS or MMK command, sit back and wait. Perl should
274compile and link without a problem. If a problem does occur check the
275"CAVEATS" section of this document. If that does not help send some
276mail to the VMSPERL mailing list. Instructions are in the "Mailing Lists"
277section of this document.
97abc6ad 278
b4bc034f 279=head1 Testing Perl
fb73857a 280
b4bc034f 281Once Perl has built cleanly you need to test it to make sure things work.
282This step is very important since there are always things that can go wrong
283somehow and yield a dysfunctional Perl for you.
fb73857a 284
285Testing is very easy, though, as there's a full test suite in the perl
b4bc034f 286distribution. To run the tests, enter the *exact* MMS line you used to
fb73857a 287compile Perl and add the word "test" to the end, like this:
288
b4bc034f 289If the compile command was:
fb73857a 290
b4bc034f 291 MMS
fb73857a 292
b4bc034f 293then the test command ought to be:
fb73857a 294
b4bc034f 295 MMS test
fb73857a 296
b4bc034f 297MMS (or MMK) will run all the tests. This may take some time, as there are
298a lot of tests. If any tests fail, there will be a note made on-screen.
299At the end of all the tests, a summary of the tests, the number passed and
300failed, and the time taken will be displayed.
fb73857a 301
96d6186e 302The test driver invoked via MMS TEST has a DCL wrapper ([.VMS]TEST.COM) that
303downgrades privileges to NETMBX, TMPMBX for the duration of the test run,
304and then restores them to their prior state upon completion of testing.
305This is done to ensure that the tests run in a private sandbox and can do no
306harm to your system even in the unlikely event something goes badly wrong in
307one of the test scripts while running the tests from a privileged account.
308A side effect of this safety precaution is that the account used to run the
309test suite must be the owner of the directory tree in which Perl has been
310built; otherwise the manipulations of temporary files and directories
311attempted by some of the tests will fail.
312
b4bc034f 313If any tests fail, it means something is wrong with Perl. If the test suite
fb73857a 314hangs (some tests can take upwards of two or three minutes, or more if
9f3f8d50 315you're on an especially slow machine, depending on your machine speed, so
fb73857a 316don't be hasty), then the test *after* the last one displayed failed. Don't
317install Perl unless you're confident that you're OK. Regardless of how
318confident you are, make a bug report to the VMSPerl mailing list.
319
b4bc034f 320If one or more tests fail, you can get more information on the failure by
321issuing this command sequence:
fb73857a 322
b4bc034f 323 @ [.VMS]TEST .typ "" "-v" [.subdir]test.T
fb73857a 324
325where ".typ" is the file type of the Perl images you just built (if you
326didn't do anything special, use .EXE), and "[.subdir]test.T" is the test
327that failed. For example, with a normal Perl build, if the test indicated
96d6186e 328that t/op/time failed, then you'd do this:
fb73857a 329
b4bc034f 330 @ [.VMS]TEST .EXE "" "-v" [.OP]TIME.T
fb73857a 331
96d6186e 332Note that test names are reported in UNIX syntax and relative to the
333top-level build directory. When supplying them individually to the test
334driver, you can use either UNIX or VMS syntax, but you must give the path
335relative to the [.T] directory and you must also add the .T extension to the
336filename. So, for example if the test lib/Math/Trig fails, you would run:
337
338 @ [.VMS]TEST .EXE "" -"v" [-.lib.math]trig.t
339
fb73857a 340When you send in a bug report for failed tests, please include the output
341from this command, which is run from the main source directory:
342
b4bc034f 343 MCR []MINIPERL "-V"
344
345Note that -"V" really is a capital V in double quotes. This will dump out a
346couple of screens worth of configuration information, and can help us
347diagnose the problem. If (and only if) that did not work then try enclosing
348the output of:
349
350 MMS printconfig
fb73857a 351
9f3f8d50 352If (and only if) that did not work then try enclosing the output of:
353
b4bc034f 354 @ [.vms]myconfig
fb73857a 355
b4bc034f 356You may also be asked to provide your C compiler version ("CC/VERSION NL:"
357with DEC C, "gcc --version" with GNU CC). To obtain the version of MMS or
358MMK you are running try "MMS/ident" or "MMK /ident". The GNU make version
359can be identified with "make --version".
360
a83b6f46 361=head2 Cleaning up and starting fresh (optional) installing Perl on VMS
fb73857a 362
363If you need to recompile from scratch, you have to make sure you clean up
b4bc034f 364first. There is a procedure to do it--enter the *exact* MMS line you used
365to compile and add "realclean" at the end, like this:
fb73857a 366
b4bc034f 367if the compile command was:
fb73857a 368
b4bc034f 369 MMS
fb73857a 370
b4bc034f 371then the cleanup command ought to be:
fb73857a 372
b4bc034f 373 MMS realclean
fb73857a 374
b4bc034f 375If you do not do this things may behave erratically during the subsequent
376rebuild attempt. They might not, too, so it is best to be sure and do it.
fb73857a 377
b4bc034f 378=head1 Installing Perl
fb73857a 379
380There are several steps you need to take to get Perl installed and
3a385817 381running.
fb73857a 382
a3ef2c6f 383=over 4
b4bc034f 384
a3ef2c6f 385=item 1
fb73857a 386
a3ef2c6f 387Check your default file protections with
fb73857a 388
a3ef2c6f 389 SHOW PROTECTION /DEFAULT
fb73857a 390
a3ef2c6f 391and adjust if necessary with SET PROTECTION=(code)/DEFAULT.
fb73857a 392
a3ef2c6f 393=item 2
3a385817 394
1bc81404 395Decide where you want Perl to be installed (unless you have already done so
396by using the "prefix" configuration parameter -- see the example in the
397"Configuring the Perl build" section).
b4bc034f 398
1bc81404 399The DCL script PERL_SETUP.COM that is written by CONFIGURE.COM will help you
400with the definition of the PERL_ROOT and PERLSHR logical names and the PERL
401foreign command symbol. Take a look at PERL_SETUP.COM and modify it if you
402want to. The installation process will execute PERL_SETUP.COM and copy
403files to the directory tree pointed to by the PERL_ROOT logical name defined
404there, so make sure that you have write access to the parent directory of
405what will become the root of your Perl installation.
fb73857a 406
a3ef2c6f 407=item 3
b4bc034f 408
a3ef2c6f 409Run the install script via:
b4bc034f 410
a3ef2c6f 411 MMS install
b4bc034f 412
a3ef2c6f 413or
9f3f8d50 414
a3ef2c6f 415 MMK install
b4bc034f 416
a3ef2c6f 417If for some reason it complains about target INSTALL being up to date,
418throw a /FORCE switch on the MMS or MMK command.
b4bc034f 419
a3ef2c6f 420=back
421
1bc81404 422Copy PERL_SETUP.COM to a place accessible to your perl users.
423
a3ef2c6f 424For example:
fb73857a 425
a3ef2c6f 426 COPY PERL_SETUP.COM SYS$LIBRARY:
b4bc034f 427
a3ef2c6f 428If you want to have everyone on the system have access to perl
429then add a line that reads
fb73857a 430
a3ef2c6f 431 $ @sys$library:perl_setup
491527d0 432
a3ef2c6f 433to SYS$MANAGER:SYLOGIN.COM.
85988417 434
a3ef2c6f 435Two alternatives to the foreign symbol would be to install PERL into
436DCLTABLES.EXE (Check out the section "Installing Perl into DCLTABLES
437(optional)" for more information), or put the image in a
438directory that's in your DCL$PATH (if you're using VMS V6.2 or higher).
85988417 439
a3ef2c6f 440An alternative to having PERL_SETUP.COM define the PERLSHR logical name
441is to simply copy it into the system shareable library directory with:
442
443 copy perl_root:[000000]perlshr.exe sys$share:
85988417 444
a3ef2c6f 445See also the "INSTALLing images (optional)" section.
491527d0 446
a83b6f46 447=head2 Installing Perl into DCLTABLES (optional) on VMS
fb73857a 448
9ef4b0a6 449Execute the following command file to define PERL as a DCL command.
b4bc034f 450You'll need CMKRNL privilege to install the new dcltables.exe.
fb73857a 451
7bb57f25 452 $ create perl.cld
453 !
454 ! modify to reflect location of your perl.exe
455 !
456 define verb perl
457 image perl_root:[000000]perl.exe
458 cliflags (foreign)
459 $!
460 $ set command perl /table=sys$common:[syslib]dcltables.exe -
461 /output=sys$common:[syslib]dcltables.exe
462 $ install replace sys$common:[syslib]dcltables.exe
463 $ exit
fb73857a 464
a83b6f46 465=head2 INSTALLing Perl images (optional) on VMS
9f3f8d50 466
467On systems that are using perl quite a bit, and particularly those with
468minimal RAM, you can boost the performance of perl by INSTALLing it as
adc5a9a5 469a known image. PERLSHR.EXE is typically larger than 3000 blocks
9f3f8d50 470and that is a reasonably large amount of IO to load each time perl is
471invoked.
472
473 INSTALL ADD PERLSHR/SHARE
b4bc034f 474 INSTALL ADD PERL/HEADER
9f3f8d50 475
476should be enough for PERLSHR.EXE (/share implies /header and /open),
477while /HEADER should do for PERL.EXE (perl.exe is not a shared image).
478
b4bc034f 479If your code 'use's modules, check to see if there is a shareable image for
480them, too. In the base perl build, POSIX, IO, Fcntl, Opcode, SDBM_File,
e7948fac 481DCLsym, and Stdio, and other extensions all have shared images that can be
482installed /SHARE.
9f3f8d50 483
b4bc034f 484How much of a win depends on your memory situation, but if you are firing
9f3f8d50 485off perl with any regularity (like more than once every 20 seconds or so)
b4bc034f 486it is probably beneficial to INSTALL at least portions of perl.
9f3f8d50 487
488While there is code in perl to remove privileges as it runs you are advised
489to NOT INSTALL PERL.EXE with PRIVs!
fb73857a 490
dab31494 491=head2 Running h2ph to create perl header files (optional) on VMS
492
493If using DEC C or Compaq C ensure that you have extracted loose versions
494of your compiler's header or *.H files. Be sure to check the contents of:
495
496 SYS$LIBRARY:DECC$RTLDEF.TLB
497 SYS$LIBRARY:SYS$LIB_C.TLB
498 SYS$LIBRARY:SYS$STARLET_C.TLB
499
500etcetera.
501
502If using GNU cc then also check your GNU_CC:[000000...] tree for the locations
503of the GNU cc headers.
504
b4bc034f 505=head1 Reporting Bugs
fb73857a 506
507If you come across what you think might be a bug in Perl, please report
508it. There's a script in PERL_ROOT:[UTILS], perlbug, that walks you through
509the process of creating a bug report. This script includes details of your
510installation, and is very handy. Completed bug reports should go to
9f3f8d50 511perlbug@perl.com.
fb73857a 512
b4bc034f 513=head1 CAVEATS
fb73857a 514
515Probably the single biggest gotcha in compiling Perl is giving the wrong
b4bc034f 516switches to MMS/MMK when you build. Use *exactly* what the configure.com
517script prints!
518
519The next big gotcha is directory depth. Perl can create directories four,
520five, or even six levels deep during the build, so you don't have to be
dab31494 521too deep to start to hit the RMS 8 level limit (for ODS 2 volumes which were
522common on versions of VMS prior to V7.2 and even with V7.2 on the VAX).
523It is best to do:
b4bc034f 524
525 DEFINE/TRANS=(CONC,TERM) PERLSRC "disk:[dir.dir.dir.perldir.]"
526 SET DEFAULT PERLSRC:[000000]
527
528before building in cases where you have to unpack the distribution so deep
529(note the trailing period in the definition of PERLSRC). Perl modules
530from CPAN can be just as bad (or worse), so watch out for them, too. Perl's
531configuration script will warn if it thinks you are too deep (at least on
532a VAX or on Alpha versions of VMS prior to 7.2). But MakeMaker will not
533warn you if you start out building a module too deep in a directory.
534
535Be sure that the process that you use to build perl has a PGFLQ greater
536than 100000. Be sure to have a correct local time zone to UTC offset
537defined (in seconds) in the logical name SYS$TIMEZONE_DIFFERENTIAL before
538running the regression test suite. The SYS$MANAGER:UTC$CONFIGURE_TDF.COM
539procedure will help you set that logical for your system but may require
540system privileges. For example, a location 5 hours west of UTC (such as
541the US East coast while not on daylight savings time) would have:
542
543 DEFINE SYS$TIMEZONE_DIFFERENTIAL "-18000"
544
545A final thing that causes trouble is leftover pieces from a failed
546build. If things go wrong make sure you do a "(MMK|MMS|make) realclean"
fb73857a 547before you rebuild.
548
a83b6f46 549=head2 DEC C issues with Perl on VMS
fb73857a 550
b4bc034f 551Note to DEC C users: Some early versions (pre-5.2, some pre-4. If you're DEC
c54e8273 552C 5.x or higher, with current patches if any, you're fine) of the DECCRTL
fb73857a 553contained a few bugs which affect Perl performance:
b4bc034f 554
555=over 4
556
557=item - pipes
558
559Newlines are lost on I/O through pipes, causing lines to run together.
560This shows up as RMS RTB errors when reading from a pipe. You can
561work around this by having one process write data to a file, and
562then having the other read the file, instead of the pipe. This is
563fixed in version 4 of DEC C.
564
565=item - modf()
566
567The modf() routine returns a non-integral value for some values above
568INT_MAX; the Perl "int" operator will return a non-integral value in
569these cases. This is fixed in version 4 of DEC C.
570
571=item - ALPACRT ECO
572
573On the AXP, if SYSNAM privilege is enabled, the CRTL chdir() routine
574changes the process default device and directory permanently, even
575though the call specified that the change should not persist after
576Perl exited. This is fixed by DEC CSC patch ALPACRT04_061 or later.
577See also:
578
172b4273 579 http://ftp.support.compaq.com/patches/.new/openvms.shtml
b4bc034f 580
581=back
582
583Please note that in later versions "DEC C" may also be known as
584"Compaq C".
585
a83b6f46 586=head2 GNU issues with Perl on VMS
b4bc034f 587
588It has been a while since the GNU utilities such as GCC or GNU make
589were used to build perl on VMS. Hence they may require a great deal
590of source code modification to work again.
591
592 http://slacvx.slac.stanford.edu/HELP/GCC
593 http://www.progis.de/
b4bc034f 594 http://www.lp.se/products/gnu.html
595
e7948fac 596=head2 Floating Point Considerations
597
598Prior to 5.8.0, Perl simply accepted the default floating point options of the
599C compiler, namely representing doubles with D_FLOAT on VAX and G_FLOAT on
600Alpha. Single precision floating point values are represented in F_FLOAT
601format when either D_FLOAT or G_FLOAT is in use for doubles. Beginning with
6025.8.0, Alpha builds now use IEEE floating point formats by default, which in
603VMS parlance are S_FLOAT for singles and T_FLOAT for doubles. IEEE is not
604available on VAX, so F_FLOAT and D_FLOAT remain the defaults for singles and
605doubles respectively. The available non-default options are G_FLOAT on VAX
606and D_FLOAT or G_FLOAT on Alpha.
607
608The use of IEEE on Alpha introduces NaN, infinity, and denormalization
609capabilities not available with D_FLOAT and G_FLOAT. When using one of those
610non-IEEE formats, silent underflow and overflow are emulated in the conversion
611of strings to numbers, but it is preferable to get the real thing by using
612IEEE where possible.
613
614Regardless of what floating point format you consider preferable, be aware
615that the choice may have an impact on compatibility with external libraries,
616such as database interfaces, and with existing data, such as data created with
617the C<pack> function and written to disk, or data stored via the Storable
618extension. For example, a C<pack("d", $foo)")> will create a D_FLOAT,
619G_FLOAT, or T_FLOAT depending on what your Perl was configured with. When
620written to disk, the value can only be retrieved later by a Perl configured
621with the same floating point option that was in effect when it was created.
622
623To obtain a non-IEEE build on Alpha, simply answer no to the "Use IEEE math?"
624question during the configuration. To obtain an option different from the C
625compiler default on either VAX or Alpha, put in the option that you want in
626answer to the "Any additional cc flags?" question. For example, to obtain a
627G_FLOAT build on VAX, put in C</FLOAT=G_FLOAT>.
628
49fd6f17 629=head2 Multinet issues with Perl on VMS
630
631Prior to the release of Perl 5.8.0 it was noted that the regression
632test for lib/Net/hostent (in file [.lib.Net]hostent.t) will fail owing
633to problems with the hostent structure returned by C calls to either
634gethostbyname() or gethostbyaddr() using DEC or Compaq C with a
635Multinet TCP/IP stack. The problem was noted in Multinet 4.3A
636using either Compaq C 6.5 or DEC C 6.0, and with Multinet 4.2A
637using DEC C 5.2, but could easily affect other versions of Multinet.
c2a352b2 638Process Software Inc. has acknowledged a bug in the Multinet version
639of UCX$IPC_SHR and has provided an ECO for it. The ECO is called
640UCX_LIBRARY_EMULATION-010_A044 and is available from:
49fd6f17 641
642 http://www.multinet.process.com/eco.html
643
c2a352b2 644As of this writing, the ECO is only available for Multinet versions
6454.3A and later. You may determine the version of Multinet that you
646are running using the command:
49fd6f17 647
648 multinet show /version
649
650from the DCL command prompt.
651
c2a352b2 652If the ECO is unavailable for your version of Multinet and you are
653unable to upgrade, you might try using Perl programming constructs
654such as:
49fd6f17 655
656 $address = substr($gethostbyname_addr,0,4);
657
658to temporarily work around the problem, or if you are brave
659and do not mind the possibility of breaking IPv6 addresses,
660you might modify the pp_sys.c file to add an ad-hoc correction
661like so:
662
663
664 --- pp_sys.c;1 Thu May 30 14:42:17 2002
665 +++ pp_sys.c Thu May 30 12:54:02 2002
666 @@ -4684,6 +4684,10 @@
667 }
668 #endif
669
670 + if (hent) {
671 + hent->h_length = 4;
672 + }
673 +
674 if (GIMME != G_ARRAY) {
675 PUSHs(sv = sv_newmortal());
676 if (hent) {
677
678then re-compile and re-test your perl. After the installation
679of the Multinet ECO you ought to back out any such changes though.
680
b4bc034f 681=head1 Mailing Lists
682
683There are several mailing lists available to the Perl porter. For VMS
fb73857a 684specific issues (including both Perl questions and installation problems)
b4bc034f 685there is the VMSPERL mailing list. It is usually a low-volume (10-12
fb73857a 686messages a week) mailing list.
687
1bc81404 688To subscribe, send a mail message to VMSPERL-SUBSCRIBE@PERL.ORG. The VMSPERL
689mailing list address is VMSPERL@PERL.ORG. Any mail sent there gets echoed
690to all subscribers of the list. There is a searchable archive of the list
691on the web at:
b4bc034f 692
693 http://www.xray.mpe.mpg.de/mailing-lists/vmsperl/
a83b6f46 694
1bc81404 695To unsubscribe from VMSPERL send a message to VMSPERL-UNSUBSCRIBE@PERL.ORG.
696Be sure to do so from the subscribed account that you are canceling.
b4bc034f 697
a83b6f46 698=head2 Web sites for Perl on VMS
b4bc034f 699
700Vmsperl pages on the web include:
701
702 http://www.sidhe.org/vmsperl/index.html
1bc81404 703 http://www.crinoid.com/
b4bc034f 704 http://duphy4.physics.drexel.edu/pub/cgi_info.htmlx
468f45d5 705 http://www.cpan.org/modules/by-module/VMS/
60d9c7be 706 http://www.xray.mpe.mpg.de/mailing-lists/vmsperl/
b4bc034f 707 http://www.best.com/~pvhp/vms/
adc5a9a5 708 http://www-ang.kfunigraz.ac.at/~binder/perl.html
60d9c7be 709 http://lists.perl.org/showlist.cgi?name=vmsperl
710 http://archive.develooper.com/vmsperl@perl.org/
adc5a9a5 711 http://www.openvms.compaq.com/openvms/products/ips/apache/csws_modperl.html
fb73857a 712
b4bc034f 713=head1 SEE ALSO
714
715Perl information for users and programmers about the port of perl to VMS is
716available from the [.VMS]PERLVMS.POD file that gets installed as L<perlvms>.
717For administrators the perlvms document also includes a detailed discussion
718of extending vmsperl with CPAN modules after Perl has been installed.
719
720=head1 AUTHORS
721
adc5a9a5 722Revised 10-October-2001 by Craig Berry craigberry@mac.com.
1bc81404 723Revised 25-February-2000 by Peter Prymmer pvhp@best.com.
724Revised 27-October-1999 by Craig Berry craigberry@mac.com.
b4bc034f 725Revised 01-March-1999 by Dan Sugalski dan@sidhe.org.
726Originally by Charles Bailey bailey@newman.upenn.edu.
727
728=head1 ACKNOWLEDGEMENTS
fb73857a 729
730A real big thanks needs to go to Charles Bailey
b4bc034f 731bailey@newman.upenn.edu, who is ultimately responsible for Perl 5.004
fb73857a 732running on VMS. Without him, nothing the rest of us have done would be at
733all important.
734
735There are, of course, far too many people involved in the porting and testing
736of Perl to mention everyone who deserves it, so please forgive us if we've
737missed someone. That said, special thanks are due to the following:
b4bc034f 738
739 Tim Adye T.J.Adye@rl.ac.uk
fb73857a 740 for the VMS emulations of getpw*()
b4bc034f 741 David Denholm denholm@conmat.phys.soton.ac.uk
fb73857a 742 for extensive testing and provision of pipe and SocketShr code,
b4bc034f 743 Mark Pizzolato mark@infocomm.com
fb73857a 744 for the getredirection() code
b4bc034f 745 Rich Salz rsalz@bbn.com
fb73857a 746 for readdir() and related routines
b4bc034f 747 Peter Prymmer pvhp@best.com
fb73857a 748 for extensive testing, as well as development work on
749 configuration and documentation for VMS Perl,
b4bc034f 750 Dan Sugalski dan@sidhe.org
fb73857a 751 for extensive contributions to recent version support,
752 development of VMS-specific extensions, and dissemination
753 of information about VMS Perl,
754 the Stanford Synchrotron Radiation Laboratory and the
755 Laboratory of Nuclear Studies at Cornell University for
9f3f8d50 756 the opportunity to test and develop for the AXP,
a3ef2c6f 757 John Hasstedt John.Hasstedt@sunysb.edu
758 for VAX VMS V7.2 support
b4bc034f 759
fb73857a 760and to the entire VMSperl group for useful advice and suggestions. In
761addition the perl5-porters deserve credit for their creativity and
762willingness to work with the VMS newcomers. Finally, the greatest debt of
b4bc034f 763gratitude is due to Larry Wall larry@wall.org, for having the ideas which
fb73857a 764have made our sleepless nights possible.
765
766Thanks,
767The VMSperl group
b4bc034f 768
769=cut
770