vmsish(3perl)
NAME
vmsish - Perl pragma to control VMS-specific language features
SYNOPSIS
use vmsish;
use vmsish 'status'; # or '$?'
use vmsish 'exit';
use vmsish 'time';
use vmsish 'hushed';
no vmsish 'hushed';
vmsish::hushed($hush);
use vmsish;
no vmsish 'time';
DESCRIPTION
If no import list is supplied, all possible VMS-specific features are
assumed. Currently, there are four VMS-specific features available:
'status' (a.k.a '$?'), 'exit', 'time' and 'hushed'.
If you're not running VMS, this module does nothing.
"vmsish status"
This makes $? and "system" return the native VMS exit status
instead of emulating the POSIX exit status.
"vmsish exit"
This makes "exit 1" produce a successful exit (with status
SS$_NORMAL), instead of emulating UNIX exit(), which considers
"exit 1" to indicate an error. As with the CRTL's exit()
function, "exit 0" is also mapped to an exit status of
SS$_NORMAL, and any other argument to exit() is used directly as
Perl's exit status.
"vmsish time"
This makes all times relative to the local time zone, instead of
the default of Universal Time (a.k.a Greenwich Mean Time, or
GMT).
"vmsish hushed"
This suppresses printing of VMS status messages to SYS$OUTPUT and
SYS$ERROR if Perl terminates with an error status, and allows
programs that are expecting "unix-style" Perl to avoid having to
parse VMS error messages. It does not suppress any messages from
Perl itself, just the messages generated by DCL after Perl exits.
The DCL symbol $STATUS will still have the termination status,
but with a high-order bit set:
EXAMPLE:
$ perl -e"exit 44;" Non-hushed error
exit
%SYSTEM-F-ABORT, abort DCL message
$ show sym $STATUS
$STATUS == "%X0000002C"
$ perl -e"use vmsish qw(hushed); exit 44;" Hushed error exit
$ show sym $STATUS
$STATUS == "%X1000002C"
The 'hushed' flag has a global scope during compilation: the
exit() or die() commands that are compiled after 'vmsish hushed'
will be hushed when they are executed. Doing a "no vmsish
'hushed'" turns off the hushed flag.
The status of the hushed flag also affects output of VMS error
messages from compilation errors. Again, you still get the Perl
error message (and the code in $STATUS)
EXAMPLE:
use vmsish 'hushed'; # turn on hushed flag
use Carp; # Carp compiled hushed
exit 44; # will be hushed
croak('I die'); # will be hushed
no vmsish 'hushed'; # turn off hushed flag
exit 44; # will not be hushed
croak('I die2'): # WILL be hushed, croak was compiled
hushed
You can also control the 'hushed' flag at run-time, using the
built-in routine vmsish::hushed(). Without argument, it returns
the hushed status. Since vmsish::hushed is built-in, you do not
need to "use vmsish" to call it.
EXAMPLE:
if ($quiet_exit) {
vmsish::hushed(1);
}
print "Sssshhhh...I'm hushed...\n" if vmsish::hushed();
exit 44;
Note that an exit() or die() that is compiled 'hushed' because of
"use vmsish" is not un-hushed by calling vmsish::hushed(0) at
runtime.
The messages from error exits from inside the Perl core are
generally more serious, and are not suppressed.
See "Perl Modules" in perlmod.
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