binmode(FH); to act like binmode(FH,":bytes") as well as
[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
179 TMP "LOGICAL"
180 LIB "LOGICAL"
181 T "LOGICAL"
182 FOO "LOGICAL"
183 EXT "LOGICAL"
184 TEST "SYMBOL"
fb73857a 185
97abc6ad 186As a handy shortcut, the command:
187
b4bc034f 188 @ Configure "-des"
189
190(note the quotation marks and case) will choose reasonable defaults
191automatically (it takes DEC C over Gnu C, DEC C sockets over SOCKETSHR
1bc81404 192sockets, and either over no sockets). Some options can be given
193explicitly on the command line; the following example specifies a
194non-default location for where Perl will be installed:
195
196 @ Configure "-d" "-Dprefix=dka100:[utils.perl5.]"
197
dab31494 198Note that the installation location would be by default where you unpacked
fe05d1a7 199the source with a "_ROOT." appended. For example if you unpacked the perl
dab31494 200source into:
201
202 DKA200:[PERL-5_10_2...]
203
adc5a9a5 204Then the PERL_SETUP.COM that gets written out by CONFIGURE.COM will
dab31494 205try to DEFINE your installation PERL_ROOT to be:
206
fe05d1a7 207 DKA200:[PERL-5_10_2_ROOT.]
dab31494 208
1bc81404 209More help with configure.com is available from:
b4bc034f 210
211 @ Configure "-h"
212
213See the "Changing compile-time options (optional)" section below to learn
214even more details about how to influence the outcome of the important
215configuration step. If you find yourself reconfiguring and rebuilding
216then be sure to also follow the advice in the "Cleaning up and starting
217fresh (optional)" and the checklist of items in the "CAVEATS" sections
218below.
219
a83b6f46 220=head2 Changing compile-time options (optional) for Perl on VMS
b4bc034f 221
222Most of the user definable features of Perl are enabled or disabled in
adc5a9a5 223configure.com, which processes the hints file config_h.SH. There is
224code in there to Do The Right Thing, but that may end up being the
225wrong thing for you. Make sure you understand what you are doing since
226inappropriate changes to configure.com or config_h.SH can render perl
227unbuildable; odds are that there's nothing in there you'll need to
228change.
b4bc034f 229
230The one exception is the various *DIR install locations. Changing those
231requires changes in genconfig.pl as well. Be really careful if you need to
232change these, as they can cause some fairly subtle problems.
233
a83b6f46 234=head2 Socket Support (optional) for Perl on VMS
b4bc034f 235
236Perl includes a number of functions for IP sockets, which are available if
237you choose to compile Perl with socket support. Since IP networking is an
238optional addition to VMS, there are several different IP stacks available.
239How well integrated they are into the system depends on the stack, your
240version of VMS, and the version of your C compiler.
241
242The most portable solution uses the SOCKETSHR library. In combination with
243either UCX or NetLib, this supports all the major TCP stacks (Multinet,
244Pathways, TCPWare, UCX, and CMU) on all versions of VMS Perl runs on, with
245all the compilers on both VAX and Alpha. The socket interface is also
246consistent across versions of VMS and C compilers. It has a problem with
247UDP sockets when used with Multinet, though, so you should be aware of
248that.
249
250The other solution available is to use the socket routines built into DEC
251C. Which routines are available depend on the version of VMS you're
252running, and require proper UCX emulation by your TCP/IP vendor.
253Relatively current versions of Multinet, TCPWare, Pathway, and UCX all
254provide the required libraries--check your manuals or release notes to see
255if your version is new enough.
256
257=head1 Building Perl
258
259The configuration script will print out, at the very end, the MMS or MMK
260command you need to compile perl. Issue it (exactly as printed) to start
261the build.
97abc6ad 262
b4bc034f 263Once you issue your MMS or MMK command, sit back and wait. Perl should
264compile and link without a problem. If a problem does occur check the
265"CAVEATS" section of this document. If that does not help send some
266mail to the VMSPERL mailing list. Instructions are in the "Mailing Lists"
267section of this document.
97abc6ad 268
b4bc034f 269=head1 Testing Perl
fb73857a 270
b4bc034f 271Once Perl has built cleanly you need to test it to make sure things work.
272This step is very important since there are always things that can go wrong
273somehow and yield a dysfunctional Perl for you.
fb73857a 274
275Testing is very easy, though, as there's a full test suite in the perl
b4bc034f 276distribution. To run the tests, enter the *exact* MMS line you used to
fb73857a 277compile Perl and add the word "test" to the end, like this:
278
b4bc034f 279If the compile command was:
fb73857a 280
b4bc034f 281 MMS
fb73857a 282
b4bc034f 283then the test command ought to be:
fb73857a 284
b4bc034f 285 MMS test
fb73857a 286
b4bc034f 287MMS (or MMK) will run all the tests. This may take some time, as there are
288a lot of tests. If any tests fail, there will be a note made on-screen.
289At the end of all the tests, a summary of the tests, the number passed and
290failed, and the time taken will be displayed.
fb73857a 291
b4bc034f 292If any tests fail, it means something is wrong with Perl. If the test suite
fb73857a 293hangs (some tests can take upwards of two or three minutes, or more if
9f3f8d50 294you're on an especially slow machine, depending on your machine speed, so
fb73857a 295don't be hasty), then the test *after* the last one displayed failed. Don't
296install Perl unless you're confident that you're OK. Regardless of how
297confident you are, make a bug report to the VMSPerl mailing list.
298
b4bc034f 299If one or more tests fail, you can get more information on the failure by
300issuing this command sequence:
fb73857a 301
b4bc034f 302 @ [.VMS]TEST .typ "" "-v" [.subdir]test.T
fb73857a 303
304where ".typ" is the file type of the Perl images you just built (if you
305didn't do anything special, use .EXE), and "[.subdir]test.T" is the test
306that failed. For example, with a normal Perl build, if the test indicated
307that [.op]time failed, then you'd do this:
308
b4bc034f 309 @ [.VMS]TEST .EXE "" "-v" [.OP]TIME.T
fb73857a 310
311When you send in a bug report for failed tests, please include the output
312from this command, which is run from the main source directory:
313
b4bc034f 314 MCR []MINIPERL "-V"
315
316Note that -"V" really is a capital V in double quotes. This will dump out a
317couple of screens worth of configuration information, and can help us
318diagnose the problem. If (and only if) that did not work then try enclosing
319the output of:
320
321 MMS printconfig
fb73857a 322
9f3f8d50 323If (and only if) that did not work then try enclosing the output of:
324
b4bc034f 325 @ [.vms]myconfig
fb73857a 326
b4bc034f 327You may also be asked to provide your C compiler version ("CC/VERSION NL:"
328with DEC C, "gcc --version" with GNU CC). To obtain the version of MMS or
329MMK you are running try "MMS/ident" or "MMK /ident". The GNU make version
330can be identified with "make --version".
331
a83b6f46 332=head2 Cleaning up and starting fresh (optional) installing Perl on VMS
fb73857a 333
334If you need to recompile from scratch, you have to make sure you clean up
b4bc034f 335first. There is a procedure to do it--enter the *exact* MMS line you used
336to compile and add "realclean" at the end, like this:
fb73857a 337
b4bc034f 338if the compile command was:
fb73857a 339
b4bc034f 340 MMS
fb73857a 341
b4bc034f 342then the cleanup command ought to be:
fb73857a 343
b4bc034f 344 MMS realclean
fb73857a 345
b4bc034f 346If you do not do this things may behave erratically during the subsequent
347rebuild attempt. They might not, too, so it is best to be sure and do it.
fb73857a 348
b4bc034f 349=head1 Installing Perl
fb73857a 350
351There are several steps you need to take to get Perl installed and
3a385817 352running.
fb73857a 353
a3ef2c6f 354=over 4
b4bc034f 355
a3ef2c6f 356=item 1
fb73857a 357
a3ef2c6f 358Check your default file protections with
fb73857a 359
a3ef2c6f 360 SHOW PROTECTION /DEFAULT
fb73857a 361
a3ef2c6f 362and adjust if necessary with SET PROTECTION=(code)/DEFAULT.
fb73857a 363
a3ef2c6f 364=item 2
3a385817 365
1bc81404 366Decide where you want Perl to be installed (unless you have already done so
367by using the "prefix" configuration parameter -- see the example in the
368"Configuring the Perl build" section).
b4bc034f 369
1bc81404 370The DCL script PERL_SETUP.COM that is written by CONFIGURE.COM will help you
371with the definition of the PERL_ROOT and PERLSHR logical names and the PERL
372foreign command symbol. Take a look at PERL_SETUP.COM and modify it if you
373want to. The installation process will execute PERL_SETUP.COM and copy
374files to the directory tree pointed to by the PERL_ROOT logical name defined
375there, so make sure that you have write access to the parent directory of
376what will become the root of your Perl installation.
fb73857a 377
a3ef2c6f 378=item 3
b4bc034f 379
a3ef2c6f 380Run the install script via:
b4bc034f 381
a3ef2c6f 382 MMS install
b4bc034f 383
a3ef2c6f 384or
9f3f8d50 385
a3ef2c6f 386 MMK install
b4bc034f 387
a3ef2c6f 388If for some reason it complains about target INSTALL being up to date,
389throw a /FORCE switch on the MMS or MMK command.
b4bc034f 390
a3ef2c6f 391=back
392
1bc81404 393Copy PERL_SETUP.COM to a place accessible to your perl users.
394
a3ef2c6f 395For example:
fb73857a 396
a3ef2c6f 397 COPY PERL_SETUP.COM SYS$LIBRARY:
b4bc034f 398
a3ef2c6f 399If you want to have everyone on the system have access to perl
400then add a line that reads
fb73857a 401
a3ef2c6f 402 $ @sys$library:perl_setup
491527d0 403
a3ef2c6f 404to SYS$MANAGER:SYLOGIN.COM.
85988417 405
a3ef2c6f 406Two alternatives to the foreign symbol would be to install PERL into
407DCLTABLES.EXE (Check out the section "Installing Perl into DCLTABLES
408(optional)" for more information), or put the image in a
409directory that's in your DCL$PATH (if you're using VMS V6.2 or higher).
85988417 410
a3ef2c6f 411An alternative to having PERL_SETUP.COM define the PERLSHR logical name
412is to simply copy it into the system shareable library directory with:
413
414 copy perl_root:[000000]perlshr.exe sys$share:
85988417 415
a3ef2c6f 416See also the "INSTALLing images (optional)" section.
491527d0 417
a83b6f46 418=head2 Installing Perl into DCLTABLES (optional) on VMS
fb73857a 419
9ef4b0a6 420Execute the following command file to define PERL as a DCL command.
b4bc034f 421You'll need CMKRNL privilege to install the new dcltables.exe.
fb73857a 422
7bb57f25 423 $ create perl.cld
424 !
425 ! modify to reflect location of your perl.exe
426 !
427 define verb perl
428 image perl_root:[000000]perl.exe
429 cliflags (foreign)
430 $!
431 $ set command perl /table=sys$common:[syslib]dcltables.exe -
432 /output=sys$common:[syslib]dcltables.exe
433 $ install replace sys$common:[syslib]dcltables.exe
434 $ exit
fb73857a 435
a83b6f46 436=head2 INSTALLing Perl images (optional) on VMS
9f3f8d50 437
438On systems that are using perl quite a bit, and particularly those with
439minimal RAM, you can boost the performance of perl by INSTALLing it as
adc5a9a5 440a known image. PERLSHR.EXE is typically larger than 3000 blocks
9f3f8d50 441and that is a reasonably large amount of IO to load each time perl is
442invoked.
443
444 INSTALL ADD PERLSHR/SHARE
b4bc034f 445 INSTALL ADD PERL/HEADER
9f3f8d50 446
447should be enough for PERLSHR.EXE (/share implies /header and /open),
448while /HEADER should do for PERL.EXE (perl.exe is not a shared image).
449
b4bc034f 450If your code 'use's modules, check to see if there is a shareable image for
451them, too. In the base perl build, POSIX, IO, Fcntl, Opcode, SDBM_File,
e7948fac 452DCLsym, and Stdio, and other extensions all have shared images that can be
453installed /SHARE.
9f3f8d50 454
b4bc034f 455How much of a win depends on your memory situation, but if you are firing
9f3f8d50 456off perl with any regularity (like more than once every 20 seconds or so)
b4bc034f 457it is probably beneficial to INSTALL at least portions of perl.
9f3f8d50 458
459While there is code in perl to remove privileges as it runs you are advised
460to NOT INSTALL PERL.EXE with PRIVs!
fb73857a 461
dab31494 462=head2 Running h2ph to create perl header files (optional) on VMS
463
464If using DEC C or Compaq C ensure that you have extracted loose versions
465of your compiler's header or *.H files. Be sure to check the contents of:
466
467 SYS$LIBRARY:DECC$RTLDEF.TLB
468 SYS$LIBRARY:SYS$LIB_C.TLB
469 SYS$LIBRARY:SYS$STARLET_C.TLB
470
471etcetera.
472
473If using GNU cc then also check your GNU_CC:[000000...] tree for the locations
474of the GNU cc headers.
475
b4bc034f 476=head1 Reporting Bugs
fb73857a 477
478If you come across what you think might be a bug in Perl, please report
479it. There's a script in PERL_ROOT:[UTILS], perlbug, that walks you through
480the process of creating a bug report. This script includes details of your
481installation, and is very handy. Completed bug reports should go to
9f3f8d50 482perlbug@perl.com.
fb73857a 483
b4bc034f 484=head1 CAVEATS
fb73857a 485
486Probably the single biggest gotcha in compiling Perl is giving the wrong
b4bc034f 487switches to MMS/MMK when you build. Use *exactly* what the configure.com
488script prints!
489
490The next big gotcha is directory depth. Perl can create directories four,
491five, or even six levels deep during the build, so you don't have to be
dab31494 492too deep to start to hit the RMS 8 level limit (for ODS 2 volumes which were
493common on versions of VMS prior to V7.2 and even with V7.2 on the VAX).
494It is best to do:
b4bc034f 495
496 DEFINE/TRANS=(CONC,TERM) PERLSRC "disk:[dir.dir.dir.perldir.]"
497 SET DEFAULT PERLSRC:[000000]
498
499before building in cases where you have to unpack the distribution so deep
500(note the trailing period in the definition of PERLSRC). Perl modules
501from CPAN can be just as bad (or worse), so watch out for them, too. Perl's
502configuration script will warn if it thinks you are too deep (at least on
503a VAX or on Alpha versions of VMS prior to 7.2). But MakeMaker will not
504warn you if you start out building a module too deep in a directory.
505
506Be sure that the process that you use to build perl has a PGFLQ greater
507than 100000. Be sure to have a correct local time zone to UTC offset
508defined (in seconds) in the logical name SYS$TIMEZONE_DIFFERENTIAL before
509running the regression test suite. The SYS$MANAGER:UTC$CONFIGURE_TDF.COM
510procedure will help you set that logical for your system but may require
511system privileges. For example, a location 5 hours west of UTC (such as
512the US East coast while not on daylight savings time) would have:
513
514 DEFINE SYS$TIMEZONE_DIFFERENTIAL "-18000"
515
516A final thing that causes trouble is leftover pieces from a failed
517build. If things go wrong make sure you do a "(MMK|MMS|make) realclean"
fb73857a 518before you rebuild.
519
a83b6f46 520=head2 DEC C issues with Perl on VMS
fb73857a 521
b4bc034f 522Note to DEC C users: Some early versions (pre-5.2, some pre-4. If you're DEC
c54e8273 523C 5.x or higher, with current patches if any, you're fine) of the DECCRTL
fb73857a 524contained a few bugs which affect Perl performance:
b4bc034f 525
526=over 4
527
528=item - pipes
529
530Newlines are lost on I/O through pipes, causing lines to run together.
531This shows up as RMS RTB errors when reading from a pipe. You can
532work around this by having one process write data to a file, and
533then having the other read the file, instead of the pipe. This is
534fixed in version 4 of DEC C.
535
536=item - modf()
537
538The modf() routine returns a non-integral value for some values above
539INT_MAX; the Perl "int" operator will return a non-integral value in
540these cases. This is fixed in version 4 of DEC C.
541
542=item - ALPACRT ECO
543
544On the AXP, if SYSNAM privilege is enabled, the CRTL chdir() routine
545changes the process default device and directory permanently, even
546though the call specified that the change should not persist after
547Perl exited. This is fixed by DEC CSC patch ALPACRT04_061 or later.
548See also:
549
172b4273 550 http://ftp.support.compaq.com/patches/.new/openvms.shtml
b4bc034f 551
552=back
553
554Please note that in later versions "DEC C" may also be known as
555"Compaq C".
556
a83b6f46 557=head2 GNU issues with Perl on VMS
b4bc034f 558
559It has been a while since the GNU utilities such as GCC or GNU make
560were used to build perl on VMS. Hence they may require a great deal
561of source code modification to work again.
562
563 http://slacvx.slac.stanford.edu/HELP/GCC
564 http://www.progis.de/
b4bc034f 565 http://www.lp.se/products/gnu.html
566
e7948fac 567=head2 Floating Point Considerations
568
569Prior to 5.8.0, Perl simply accepted the default floating point options of the
570C compiler, namely representing doubles with D_FLOAT on VAX and G_FLOAT on
571Alpha. Single precision floating point values are represented in F_FLOAT
572format when either D_FLOAT or G_FLOAT is in use for doubles. Beginning with
5735.8.0, Alpha builds now use IEEE floating point formats by default, which in
574VMS parlance are S_FLOAT for singles and T_FLOAT for doubles. IEEE is not
575available on VAX, so F_FLOAT and D_FLOAT remain the defaults for singles and
576doubles respectively. The available non-default options are G_FLOAT on VAX
577and D_FLOAT or G_FLOAT on Alpha.
578
579The use of IEEE on Alpha introduces NaN, infinity, and denormalization
580capabilities not available with D_FLOAT and G_FLOAT. When using one of those
581non-IEEE formats, silent underflow and overflow are emulated in the conversion
582of strings to numbers, but it is preferable to get the real thing by using
583IEEE where possible.
584
585Regardless of what floating point format you consider preferable, be aware
586that the choice may have an impact on compatibility with external libraries,
587such as database interfaces, and with existing data, such as data created with
588the C<pack> function and written to disk, or data stored via the Storable
589extension. For example, a C<pack("d", $foo)")> will create a D_FLOAT,
590G_FLOAT, or T_FLOAT depending on what your Perl was configured with. When
591written to disk, the value can only be retrieved later by a Perl configured
592with the same floating point option that was in effect when it was created.
593
594To obtain a non-IEEE build on Alpha, simply answer no to the "Use IEEE math?"
595question during the configuration. To obtain an option different from the C
596compiler default on either VAX or Alpha, put in the option that you want in
597answer to the "Any additional cc flags?" question. For example, to obtain a
598G_FLOAT build on VAX, put in C</FLOAT=G_FLOAT>.
599
49fd6f17 600=head2 Multinet issues with Perl on VMS
601
602Prior to the release of Perl 5.8.0 it was noted that the regression
603test for lib/Net/hostent (in file [.lib.Net]hostent.t) will fail owing
604to problems with the hostent structure returned by C calls to either
605gethostbyname() or gethostbyaddr() using DEC or Compaq C with a
606Multinet TCP/IP stack. The problem was noted in Multinet 4.3A
607using either Compaq C 6.5 or DEC C 6.0, and with Multinet 4.2A
608using DEC C 5.2, but could easily affect other versions of Multinet.
609A representative of Process Software Inc. has acknowledged a
610bug in the Multinet version of UCX$IPC_SHR for which there is
611an ECO forthcoming. If you see one or more tests in lib/Net/hostent
612fail we recommend that you apply the Multinet ECO when it becomes
613available from:
614
615 http://www.multinet.process.com/eco.html
616
617You may determine the version of Multinet that you are running using
618the command:
619
620 multinet show /version
621
622from the DCL command prompt.
623
624If you cannot wait for the ECO from Process you might try using
625Perl programming constructs such as:
626
627 $address = substr($gethostbyname_addr,0,4);
628
629to temporarily work around the problem, or if you are brave
630and do not mind the possibility of breaking IPv6 addresses,
631you might modify the pp_sys.c file to add an ad-hoc correction
632like so:
633
634
635 --- pp_sys.c;1 Thu May 30 14:42:17 2002
636 +++ pp_sys.c Thu May 30 12:54:02 2002
637 @@ -4684,6 +4684,10 @@
638 }
639 #endif
640
641 + if (hent) {
642 + hent->h_length = 4;
643 + }
644 +
645 if (GIMME != G_ARRAY) {
646 PUSHs(sv = sv_newmortal());
647 if (hent) {
648
649then re-compile and re-test your perl. After the installation
650of the Multinet ECO you ought to back out any such changes though.
651
b4bc034f 652=head1 Mailing Lists
653
654There are several mailing lists available to the Perl porter. For VMS
fb73857a 655specific issues (including both Perl questions and installation problems)
b4bc034f 656there is the VMSPERL mailing list. It is usually a low-volume (10-12
fb73857a 657messages a week) mailing list.
658
1bc81404 659To subscribe, send a mail message to VMSPERL-SUBSCRIBE@PERL.ORG. The VMSPERL
660mailing list address is VMSPERL@PERL.ORG. Any mail sent there gets echoed
661to all subscribers of the list. There is a searchable archive of the list
662on the web at:
b4bc034f 663
664 http://www.xray.mpe.mpg.de/mailing-lists/vmsperl/
a83b6f46 665
1bc81404 666To unsubscribe from VMSPERL send a message to VMSPERL-UNSUBSCRIBE@PERL.ORG.
667Be sure to do so from the subscribed account that you are canceling.
b4bc034f 668
a83b6f46 669=head2 Web sites for Perl on VMS
b4bc034f 670
671Vmsperl pages on the web include:
672
673 http://www.sidhe.org/vmsperl/index.html
1bc81404 674 http://www.crinoid.com/
b4bc034f 675 http://duphy4.physics.drexel.edu/pub/cgi_info.htmlx
468f45d5 676 http://www.cpan.org/modules/by-module/VMS/
60d9c7be 677 http://www.xray.mpe.mpg.de/mailing-lists/vmsperl/
b4bc034f 678 http://www.best.com/~pvhp/vms/
adc5a9a5 679 http://www-ang.kfunigraz.ac.at/~binder/perl.html
60d9c7be 680 http://lists.perl.org/showlist.cgi?name=vmsperl
681 http://archive.develooper.com/vmsperl@perl.org/
adc5a9a5 682 http://www.openvms.compaq.com/openvms/products/ips/apache/csws_modperl.html
fb73857a 683
b4bc034f 684=head1 SEE ALSO
685
686Perl information for users and programmers about the port of perl to VMS is
687available from the [.VMS]PERLVMS.POD file that gets installed as L<perlvms>.
688For administrators the perlvms document also includes a detailed discussion
689of extending vmsperl with CPAN modules after Perl has been installed.
690
691=head1 AUTHORS
692
adc5a9a5 693Revised 10-October-2001 by Craig Berry craigberry@mac.com.
1bc81404 694Revised 25-February-2000 by Peter Prymmer pvhp@best.com.
695Revised 27-October-1999 by Craig Berry craigberry@mac.com.
b4bc034f 696Revised 01-March-1999 by Dan Sugalski dan@sidhe.org.
697Originally by Charles Bailey bailey@newman.upenn.edu.
698
699=head1 ACKNOWLEDGEMENTS
fb73857a 700
701A real big thanks needs to go to Charles Bailey
b4bc034f 702bailey@newman.upenn.edu, who is ultimately responsible for Perl 5.004
fb73857a 703running on VMS. Without him, nothing the rest of us have done would be at
704all important.
705
706There are, of course, far too many people involved in the porting and testing
707of Perl to mention everyone who deserves it, so please forgive us if we've
708missed someone. That said, special thanks are due to the following:
b4bc034f 709
710 Tim Adye T.J.Adye@rl.ac.uk
fb73857a 711 for the VMS emulations of getpw*()
b4bc034f 712 David Denholm denholm@conmat.phys.soton.ac.uk
fb73857a 713 for extensive testing and provision of pipe and SocketShr code,
b4bc034f 714 Mark Pizzolato mark@infocomm.com
fb73857a 715 for the getredirection() code
b4bc034f 716 Rich Salz rsalz@bbn.com
fb73857a 717 for readdir() and related routines
b4bc034f 718 Peter Prymmer pvhp@best.com
fb73857a 719 for extensive testing, as well as development work on
720 configuration and documentation for VMS Perl,
b4bc034f 721 Dan Sugalski dan@sidhe.org
fb73857a 722 for extensive contributions to recent version support,
723 development of VMS-specific extensions, and dissemination
724 of information about VMS Perl,
725 the Stanford Synchrotron Radiation Laboratory and the
726 Laboratory of Nuclear Studies at Cornell University for
9f3f8d50 727 the opportunity to test and develop for the AXP,
a3ef2c6f 728 John Hasstedt John.Hasstedt@sunysb.edu
729 for VAX VMS V7.2 support
b4bc034f 730
fb73857a 731and to the entire VMSperl group for useful advice and suggestions. In
732addition the perl5-porters deserve credit for their creativity and
733willingness to work with the VMS newcomers. Finally, the greatest debt of
b4bc034f 734gratitude is due to Larry Wall larry@wall.org, for having the ideas which
fb73857a 735have made our sleepless nights possible.
736
737Thanks,
738The VMSperl group
b4bc034f 739
740=cut
741