freebsd-dev/contrib/perl5/lib/Shell.pm

127 lines
2.1 KiB
Perl

package Shell;
use Config;
sub import {
my $self = shift;
my ($callpack, $callfile, $callline) = caller;
my @EXPORT;
if (@_) {
@EXPORT = @_;
}
else {
@EXPORT = 'AUTOLOAD';
}
foreach $sym (@EXPORT) {
*{"${callpack}::$sym"} = \&{"Shell::$sym"};
}
};
AUTOLOAD {
my $cmd = $AUTOLOAD;
$cmd =~ s/^.*:://;
eval qq {
*$AUTOLOAD = sub {
if (\@_ < 1) {
`$cmd`;
}
elsif (\$Config{'archname'} eq 'os2') {
local(\*SAVEOUT, \*READ, \*WRITE);
open SAVEOUT, '>&STDOUT' or die;
pipe READ, WRITE or die;
open STDOUT, '>&WRITE' or die;
close WRITE;
my \$pid = system(1, \$cmd, \@_);
die "Can't execute $cmd: \$!\n" if \$pid < 0;
open STDOUT, '>&SAVEOUT' or die;
close SAVEOUT;
if (wantarray) {
my \@ret = <READ>;
close READ;
waitpid \$pid, 0;
\@ret;
}
else {
local(\$/) = undef;
my \$ret = <READ>;
close READ;
waitpid \$pid, 0;
\$ret;
}
}
else {
open(SUBPROC, "-|")
or exec '$cmd', \@_
or die "Can't exec $cmd: \$!\n";
if (wantarray) {
my \@ret = <SUBPROC>;
close SUBPROC; # XXX Oughta use a destructor.
\@ret;
}
else {
local(\$/) = undef;
my \$ret = <SUBPROC>;
close SUBPROC;
\$ret;
}
}
}
};
goto &$AUTOLOAD;
}
1;
__END__
=head1 NAME
Shell - run shell commands transparently within perl
=head1 SYNOPSIS
See below.
=head1 DESCRIPTION
Date: Thu, 22 Sep 94 16:18:16 -0700
Message-Id: <9409222318.AA17072@scalpel.netlabs.com>
To: perl5-porters@isu.edu
From: Larry Wall <lwall@scalpel.netlabs.com>
Subject: a new module I just wrote
Here's one that'll whack your mind a little out.
#!/usr/bin/perl
use Shell;
$foo = echo("howdy", "<funny>", "world");
print $foo;
$passwd = cat("</etc/passwd");
print $passwd;
sub ps;
print ps -ww;
cp("/etc/passwd", "/tmp/passwd");
That's maybe too gonzo. It actually exports an AUTOLOAD to the current
package (and uncovered a bug in Beta 3, by the way). Maybe the usual
usage should be
use Shell qw(echo cat ps cp);
Larry
=head1 AUTHOR
Larry Wall
=cut