Directions for building and installing Perl 5 can be found in
the file F<README.vms> in the main source directory of the
-Perl distribution..
+Perl distribution.
=head1 Organization of Perl Images
=head2 Core Images
-During the installation process, three Perl images are produced.
+During the build process, three Perl images are produced.
F<Miniperl.Exe> is an executable image which contains all of
the basic functionality of Perl, but cannot take advantage of
-Perl extensions. It is used to generate several files needed
-to build the complete Perl and various extensions. Once you've
-finished installing Perl, you can delete this image.
-
-Most of the complete Perl resides in the shareable image
-F<PerlShr.Exe>, which provides a core to which the Perl executable
-image and all Perl extensions are linked. You should place this
-image in F<Sys$Share>, or define the logical name F<PerlShr> to
-translate to the full file specification of this image. It should
-be world readable. (Remember that if a user has execute only access
-to F<PerlShr>, VMS will treat it as if it were a privileged shareable
-image, and will therefore require all downstream shareable images to be
-INSTALLed, etc.)
-
+Perl XS extensions and has a hard-wired list of library locations
+for loading pure-Perl modules. It is used extensively to build and
+test Perl and various extensions, but is not installed.
+
+Most of the complete Perl resides in the shareable image F<PerlShr.Exe>,
+which provides a core to which the Perl executable image and all Perl
+extensions are linked. It is generally located via the logical name
+F<PERLSHR>. While it's possible to put the image in F<SYS$SHARE> to
+make it loadable, that's not recommended. And while you may wish to
+INSTALL the image for performance reasons, you should not install it
+with privileges; if you do, the result will not be what you expect as
+image privileges are disabled during Perl start-up.
Finally, F<Perl.Exe> is an executable image containing the main
entry point for Perl, as well as some initialization code. It
$ mmk test ! Run test code, if supplied
$ mmk install ! Install into public Perl tree
-I<N.B.> The procedure by which extensions are built and
-tested creates several levels (at least 4) under the
-directory in which the extension's source files live.
-For this reason if you are running a version of VMS prior
-to V7.1 you shouldn't nest the source directory
-too deeply in your directory structure lest you exceed RMS'
-maximum of 8 levels of subdirectory in a filespec. (You
-can use rooted logical names to get another 8 levels of
-nesting, if you can't place the files near the top of
-the physical directory structure.)
-
VMS support for this process in the current release of Perl
-is sufficient to handle most extensions. However, it does
-not yet recognize extra libraries required to build shareable
-images which are part of an extension, so these must be added
-to the linker options file for the extension by hand. For
-instance, if the F<PGPLOT> extension to Perl requires the
-F<PGPLOTSHR.EXE> shareable image in order to properly link
-the Perl extension, then the line C<PGPLOTSHR/Share> must
-be added to the linker options file F<PGPLOT.Opt> produced
-during the build process for the Perl extension.
-
-By default, the shareable image for an extension is placed in
-the F<[.lib.site_perl.auto>I<Arch>.I<Extname>F<]> directory of the
-installed Perl directory tree (where I<Arch> is F<VMS_VAX> or
-F<VMS_AXP>, and I<Extname> is the name of the extension, with
-each C<::> translated to C<.>). (See the MakeMaker documentation
-for more details on installation options for extensions.)
-However, it can be manually placed in any of several locations:
+is sufficient to handle most extensions. (See the MakeMaker
+documentation for more details on installation options for
+extensions.)
=over 4
routine to force it to that format.
The feature logical name DECC$FILENAME_UNIX_REPORT modifies traditional
-Perl behavior in the conversion of file specifications from UNIX to VMS
+Perl behavior in the conversion of file specifications from Unix to VMS
format in order to follow the extended character handling rules now
expected by the CRTL. Specifically, when this feature is in effect, the
-C<./.../> in a UNIX path is now translated to C<[.^.^.^.]> instead of
+C<./.../> in a Unix path is now translated to C<[.^.^.^.]> instead of
the traditional VMS C<[...]>. To be compatible with what MakeMaker
-expects, if a VMS path cannot be translated to a UNIX path, it is
+expects, if a VMS path cannot be translated to a Unix path, it is
passed through unchanged, so C<unixify("[...]")> will return C<[...]>.
-The handling of extended characters is largely complete in the
-VMS-specific C infrastructure of Perl, but more work is still needed to
-fully support extended syntax filenames in several core modules. In
-particular, at this writing PathTools has only partial support for
-directories containing some extended characters.
-
There are several ambiguous cases where a conversion routine cannot
-determine whether an input filename is in UNIX format or in VMS format,
-since now both VMS and UNIX file specifications may have characters in
+determine whether an input filename is in Unix format or in VMS format,
+since now both VMS and Unix file specifications may have characters in
them that could be mistaken for syntax delimiters of the other type. So
some pathnames simply cannot be used in a mode that allows either type
of pathname to be present. Perl will tend to assume that an ambiguous
-filename is in UNIX format.
+filename is in Unix format.
Allowing "." as a version delimiter is simply incompatible with
-determining whether a pathname is in VMS format or in UNIX format with
+determining whether a pathname is in VMS format or in Unix format with
extended file syntax. There is no way to know whether "perl-5.8.6" is a
-UNIX "perl-5.8.6" or a VMS "perl-5.8;6" when passing it to unixify() or
+Unix "perl-5.8.6" or a VMS "perl-5.8;6" when passing it to unixify() or
vmsify().
The DECC$FILENAME_UNIX_REPORT logical name controls how Perl interprets
filenames to the extent that Perl uses the CRTL internally for many
purposes, and attempts to follow CRTL conventions for reporting
filenames. The DECC$FILENAME_UNIX_ONLY feature differs in that it
-expects all filenames passed to the C run-time to be already in UNIX
+expects all filenames passed to the C run-time to be already in Unix
format. This feature is not yet supported in Perl since Perl uses
traditional OpenVMS file specifications internally and in the test
harness, and it is not yet clear whether this mode will be useful or
=head2 Filename Case
-Perl follows VMS defaults and override settings in preserving (or not
-preserving) filename case. Case is not preserved on ODS-2 formatted
-volumes on any architecture. On ODS-5 volumes, filenames may be case
-preserved depending on process and feature settings. Perl now honors
-DECC$EFS_CASE_PRESERVE and DECC$ARGV_PARSE_STYLE on those systems where
-the CRTL supports these features. When these features are not enabled
-or the CRTL does not support them, Perl follows the traditional CRTL
-behavior of downcasing command-line arguments and returning file
-specifications in lower case only.
+Perl enables DECC$EFS_CASE_PRESERVE and DECC$ARGV_PARSE_STYLE by
+default. Note that the latter only takes effect when extended parse
+is set in the process in which Perl is running. When these features
+are explicitly disabled in the environment or the CRTL does not support
+them, Perl follows the traditional CRTL behavior of downcasing command-line
+arguments and returning file specifications in lower case only.
I<N. B.> It is very easy to get tripped up using a mixture of other
programs, external utilities, and Perl scripts that are in varying
such as MMK or MMS may generate a filename in all upper case even on an
ODS-5 volume. If this filename is later retrieved by a Perl script or
module in a case preserving environment, that upper case name may not
-match the mixed-case or lower-case expections of the Perl code. Your
+match the mixed-case or lower-case expectations of the Perl code. Your
best bet is to follow an all-or-nothing approach to case preservation:
either don't use it at all, or make sure your entire toolchain and
application environment support and use it.
OpenVMS Alpha v7.3-1 and later and all version of OpenVMS I64 support
case sensitivity as a process setting (see C<SET PROCESS
-/CASE_LOOKUP=SENSITIVE>). Perl does not currently suppport case
+/CASE_LOOKUP=SENSITIVE>). Perl does not currently support case
sensitivity on VMS, but it may in the future, so Perl programs should
-use the C<File::Spec->case_tolerant> method to determine the state, and
+use the C<< File::Spec->case_tolerant >> method to determine the state, and
not the C<$^O> variable.
=head2 Symbolic Links
in the filesystem and CRTL (generally 64-bit OpenVMS v8.3 and later).
There are a number of limitations and caveats to be aware of when
working with symbolic links on VMS. Most notably, the target of a valid
-symbolic link must be expressed as a UNIX-style path and it must exist
+symbolic link must be expressed as a Unix-style path and it must exist
on a volume visible from your POSIX root (see the C<SHOW ROOT> command
in DCL help). For further details on symbolic link capabilities and
requirements, see chapter 12 of the CRTL manual that ships with OpenVMS
Perl will wait for the subprocess to complete before continuing.
The mailbox (MBX) that perl can create to communicate with a pipe
-defaults to a buffer size of 512. The default buffer size is
-adjustable via the logical name PERL_MBX_SIZE provided that the
-value falls between 128 and the SYSGEN parameter MAXBUF inclusive.
-For example, to double the MBX size from the default within
-a Perl program, use C<$ENV{'PERL_MBX_SIZE'} = 1024;> and then
-open and use pipe constructs. An alternative would be to issue
-the command:
+defaults to a buffer size of 8192 on 64-bit systems, 512 on VAX. The
+default buffer size is adjustable via the logical name PERL_MBX_SIZE
+provided that the value falls between 128 and the SYSGEN parameter
+MAXBUF inclusive. For example, to set the mailbox size to 32767 use
+C<$ENV{'PERL_MBX_SIZE'} = 32767;> and then open and use pipe constructs.
+An alternative would be to issue the command:
- $ Define PERL_MBX_SIZE 1024
+ $ Define PERL_MBX_SIZE 32767
before running your wide record pipe program. A larger value may
improve performance at the expense of the BYTLM UAF quota.
=head1 PERL5LIB and PERLLIB
-The PERL5LIB and PERLLIB logical names work as documented in L<perl>,
-except that the element separator is '|' instead of ':'. The
+The PERL5LIB and PERLLIB environment elements work as documented in L<perl>,
+except that the element separator is, by default, '|' instead of ':'.
+However, when running under a Unix shell as determined by the logical
+name C<GNV$UNIX_SHELL>, the separator will be ':' as on Unix systems. The
directory specifications may use either VMS or Unix syntax.
=head1 The Perl Forked Debugger
$define DISPLAY "hostname:0.0"
Currently the value of C<DISPLAY> is ignored. It is recommended that it be set
-to be the hostname of the display, the server and screen in UNIX notation. In
+to be the hostname of the display, the server and screen in Unix notation. In
the future the value of DISPLAY may be honored by Perl instead of using the
default display.
This allows the programmer to look at the execution stack and variables to
find out the cause of the exception. As the debugger is being invoked as
the Perl interpreter is about to do a fatal exit, continuing the execution
-in debug mode is usally not practical.
+in debug mode is usually not practical.
Starting Perl in the VMS debugger may change the program execution
profile in a way that such problems are not reproduced.
caller, chdir, chmod, chown, chomp, chop, chr,
close, closedir, cos, crypt*, defined, delete, die, do, dump*,
each, endgrent, endpwent, eof, eval, exec*, exists, exit, exp,
- fileno, flock getc, getgrent*, getgrgid*, getgrnam, getlogin, getppid,
- getpwent*, getpwnam*, getpwuid*, glob, gmtime*, goto,
+ fileno, flock getc, getgrent*, getgrgid*, getgrnam, getlogin,
+ getppid, getpwent*, getpwnam*, getpwuid*, glob, gmtime*, goto,
grep, hex, ioctl, import, index, int, join, keys, kill*,
- last, lc, lcfirst, lchown*, length, link*, local, localtime, log, lstat, m//,
- map, mkdir, my, next, no, oct, open, opendir, ord, pack,
- pipe, pop, pos, print, printf, push, q//, qq//, qw//,
- qx//*, quotemeta, rand, read, readdir, readlink*, redo, ref, rename,
- require, reset, return, reverse, rewinddir, rindex,
+ last, lc, lcfirst, lchown*, length, link*, local, localtime, log,
+ lstat, m//, map, mkdir, my, next, no, oct, open, opendir, ord,
+ pack, pipe, pop, pos, print, printf, push, q//, qq//, qw//,
+ qx//*, quotemeta, rand, read, readdir, readlink*, redo, ref,
+ rename, require, reset, return, reverse, rewinddir, rindex,
rmdir, s///, scalar, seek, seekdir, select(internal),
select (system call)*, setgrent, setpwent, shift, sin, sleep,
socketpair, sort, splice, split, sprintf, sqrt, srand, stat,
When C<PERL_VMS_POSIX_EXIT> is active (see L</"$?"> below), the native VMS exit
status value will have either one of the C<$!> or C<$?> or C<$^E> or
-the UNIX value 255 encoded into it in a way that the effective original
+the Unix value 255 encoded into it in a way that the effective original
value can be decoded by other programs written in C, including Perl
and the GNV package. As per the normal non-VMS behavior of C<die> if
either C<$!> or C<$?> are non-zero, one of those values will be
-encoded into a native VMS status value. If both of the UNIX status
+encoded into a native VMS status value. If both of the Unix status
values are 0, and the C<$^E> value is set one of ERROR or SEVERE_ERROR
severity, then the C<$^E> value will be used as the exit code as is.
-If none of the above apply, the UNIX value of 255 will be encoded into
+If none of the above apply, the Unix value of 255 will be encoded into
a native VMS exit status value.
Please note a significant difference in the behavior of C<die> in
the C<PERL_VMS_POSIX_EXIT> mode is that it does not force a VMS
-SEVERE_ERROR status on exit. The UNIX exit values of 2 through
+SEVERE_ERROR status on exit. The Unix exit values of 2 through
255 will be encoded in VMS status values with severity levels of
-SUCCESS. The UNIX exit value of 1 will be encoded in a VMS status
+SUCCESS. The Unix exit value of 1 will be encoded in a VMS status
value with a severity level of ERROR. This is to be compatible with
how the VMS C library encodes these values.
may be changed to be ERROR or higher in the future depending on the
results of testing and further review.
-See L</"$?"> for a description of the encoding of the UNIX value to
+See L</"$?"> for a description of the encoding of the Unix value to
produce a native VMS status containing it.
-
=item dump
Rather than causing Perl to abort and dump core, the C<dump>
there is no difference between "user time" and "system" time
under VMS, and the time accumulated by a subprocess may or may
not appear separately in the "child time" field, depending on
-whether L<times> keeps track of subprocesses separately. Note
+whether C<times()> keeps track of subprocesses separately. Note
especially that the VAXCRTL (at least) keeps track only of
-subprocesses spawned using L<fork> and L<exec>; it will not
-accumulate the times of subprocesses spawned via pipes, L<system>,
+subprocesses spawned using C<fork()> and C<exec()>; it will not
+accumulate the times of subprocesses spawned via pipes, C<system()>,
or backticks.
=item unlink LIST
=item CRTL_ENV
-This string tells Perl to consult the CRTL's internal C<environ>
-array of key-value pairs, using I<name> as the key. In most cases,
-this contains only a few keys, but if Perl was invoked via the C
-C<exec[lv]e()> function, as is the case for CGI processing by some
-HTTP servers, then the C<environ> array may have been populated by
-the calling program.
+This string tells Perl to consult the CRTL's internal C<environ> array
+of key-value pairs, using I<name> as the key. In most cases, this
+contains only a few keys, but if Perl was invoked via the C
+C<exec[lv]e()> function, as is the case for some embedded Perl
+applications or when running under a shell such as GNV bash, the
+C<environ> array may have been populated by the calling program.
=item CLISYM_[LOCAL]
you make while Perl is running do not affect the behavior of C<%ENV>.
If F<PERL_ENV_TABLES> is not defined, then Perl defaults to consulting
first the logical name tables specified by F<LNM$FILE_DEV>, and then
-the CRTL C<environ> array.
+the CRTL C<environ> array. This default order is reversed when the
+logical name F<GNV$UNIX_SHELL> is defined, such as when running under
+GNV bash.
-In all operations on %ENV, the key string is treated as if it
-were entirely uppercase, regardless of the case actually
-specified in the Perl expression.
+For operations on %ENV entries based on logical names or DCL symbols, the
+key string is treated as if it were entirely uppercase, regardless of the
+case actually specified in the Perl expression. Entries in %ENV based on the
+CRTL's environ array preserve the case of the key string when stored, and
+lookups are case sensitive.
When an element of C<%ENV> is read, the locations to which
F<PERL_ENV_TABLES> points are checked in order, and the value
(The same is done if an existing logical name was defined in
executive or kernel mode; an existing user or supervisor mode
logical name is reset to the new value.) If the value is an empty
-string, the logical name's translation is defined as a single NUL
-(ASCII 00) character, since a logical name cannot translate to a
+string, the logical name's translation is defined as a single C<NUL>
+(ASCII C<\0>) character, since a logical name cannot translate to a
zero-length string. (This restriction does not apply to CLI symbols
or CRTL C<environ> values; they are set to the empty string.)
-An element of the CRTL C<environ> array can be set only if your
-copy of Perl knows about the CRTL's C<setenv()> function. (This is
-present only in some versions of the DECCRTL; check C<$Config{d_setenv}>
-to see whether your copy of Perl was built with a CRTL that has this
-function.)
-
-When an element of C<%ENV> is set to C<undef>,
-the element is looked up as if it were being read, and if it is
-found, it is deleted. (An item "deleted" from the CRTL C<environ>
-array is set to the empty string; this can only be done if your
-copy of Perl knows about the CRTL C<setenv()> function.) Using
-C<delete> to remove an element from C<%ENV> has a similar effect,
-but after the element is deleted, another attempt is made to
-look up the element, so an inner-mode logical name or a name in
-another location will replace the logical name just deleted.
-In either case, only the first value found searching PERL_ENV_TABLES
-is altered. It is not possible at present to define a search list
+
+When an element of C<%ENV> is set to C<undef>, the element is looked
+up as if it were being read, and if it is found, it is deleted. (An
+item "deleted" from the CRTL C<environ> array is set to the empty
+string.) Using C<delete> to remove an element from C<%ENV> has a
+similar effect, but after the element is deleted, another attempt is
+made to look up the element, so an inner-mode logical name or a name
+in another location will replace the logical name just deleted. In
+either case, only the first value found searching PERL_ENV_TABLES is
+altered. It is not possible at present to define a search list
logical name via %ENV.
The element C<$ENV{DEFAULT}> is special: when read, it returns
process-permanent files, such as C<SYS$INPUT> and C<SYS$OUTPUT>.
The translations for these logical names are prepended with a
two-byte binary value (0x1B 0x00) that needs to be stripped off
-if you wantto use it. (In previous versions of Perl it wasn't
+if you want to use it. (In previous versions of Perl it wasn't
possible to get the values of these logical names, as the null
byte acted as an end-of-string marker)
contain the actual value of 0 to 255 returned by that program
on a normal exit.
-With the _POSIX_EXIT macro set, the UNIX exit value of zero is
-represented as a VMS native status of 1, and the UNIX values
+With the _POSIX_EXIT macro set, the Unix exit value of zero is
+represented as a VMS native status of 1, and the Unix values
from 2 to 255 are encoded by the equation:
VMS_status = 0x35a000 + (unix_value * 8) + 1.
-And in the special case of unix value 1 the encoding is:
+And in the special case of Unix value 1 the encoding is:
VMS_status = 0x35a000 + 8 + 2 + 0x10000000.
For other termination statuses, the severity portion of the
-subprocess' exit status is used: if the severity was success or
+subprocess's exit status is used: if the severity was success or
informational, these bits are all 0; if the severity was
warning, they contain a value of 1; if the severity was
error or fatal error, they contain the actual severity bits,
which turns out to be a value of 2 for error and 4 for severe_error.
Fatal is another term for the severe_error status.
-As a result, C<$?> will always be zero if the subprocess' exit
+As a result, C<$?> will always be zero if the subprocess's exit
status indicated successful completion, and non-zero if a
warning or error occurred or a program compliant with encoding
_POSIX_EXIT values was run and set a status.
How can you tell the difference between a non-zero status that is
-the result of a VMS native error status or an encoded UNIX status?
+the result of a VMS native error status or an encoded Unix status?
You can not unless you look at the ${^CHILD_ERROR_NATIVE} value.
The ${^CHILD_ERROR_NATIVE} value returns the actual VMS status value
and check the severity bits. If the severity bits are equal to 1,
then if the numeric value for C<$?> is between 2 and 255 or 0, then
-C<$?> accurately reflects a value passed back from a UNIX application.
+C<$?> accurately reflects a value passed back from a Unix application.
If C<$?> is 1, and the severity bits indicate a VMS error (2), then
-C<$?> is from a UNIX application exit value.
+C<$?> is from a Unix application exit value.
In practice, Perl scripts that call programs that return _POSIX_EXIT
type status values will be expecting those values, and programs that
And success is always the value 0 in all behaviors.
When the actual VMS termination status of the child is an error,
-internally the C<$!> value will be set to the closest UNIX errno
+internally the C<$!> value will be set to the closest Unix errno
value to that error so that Perl scripts that test for error
-messages will see the expected UNIX style error message instead
+messages will see the expected Unix style error message instead
of a VMS message.
Conversely, when setting C<$?> in an END block, an attempt is made
almost a NOOP as it will cause the current native VMS status in the
C library to become the current native Perl VMS status, and is handled
this way as it is known to not be a valid native VMS status value.
-It is recommend that only values in the range of normal UNIX parent or
+It is recommend that only values in the range of normal Unix parent or
child status numbers, 0 to 255 are used.
The pragma C<use vmsish 'status'> makes C<$?> reflect the actual
improvements in the POSIX exit handling.
In general, with C<PERL_VMS_POSIX_EXIT> enabled, more detailed information
-will be availble in the exit status for DCL scripts or other native VMS tools,
+will be available in the exit status for DCL scripts or other native VMS tools,
and will give the expected information for Posix programs. It has not been
made the default in order to preserve backward compatibility.
https://perl5.git.perl.org / perl5.git / blobdiff