Re^4: Multiple commands with one system call

The error is not very descriptive but here it is

Too many arguments for open at /home/vpoint/testing.pl line 10, near "
+'/bin/bash' )
    "
Execution of /home/vpoint/testing.pl aborted due to compilation errors
+.
[download]

I was trying to use the code exactly as you posted it. The only thing I removed was use warnings. The OS I am using is

SunOS ferb 5.8 Generic_117350-21 sun4u sparc SUNW,Ultra-80

This is the perl version in case it helps.

perl, version 5.005_03 built for sun4-solari

Comment on Re^4: Multiple commands with one system call Select or Download Code

Replies are listed 'Best First'.
Re^5: Multiple commands with one system call by graff (Chancellor) on Oct 13, 2011 at 19:28 UTC
perl, version 5.005_03 built for sun4-solari That explains it. Your ancient SunOS system is using an ancient Perl release. The code I posted requires Perl 5.8 or later, due to its use of the "3-argument" form of the open call, which wasn't available in perl 5.5 (which is what you have in this case). Sorry, I just assumed that no one would still be using such an old version of Perl. To fix that, use the "2-argument" form for the open call -- like this: `#!/usr/bin/perl use strict; use warnings; my @cmd_list = ( 'echo 1', 'echo 2', 'echo 3', 'echo 4' ); $\|++; # turn off buffering my $shpid = open( my $sh, '\|/bin/bash' ) or die "Can't open a shell process: $!\n"; for my $cmd ( @cmd_list ) { print $sh "$cmd\n"; } print $sh "exit\n"; close $sh; waitpid( $shpid, 0 ); print "Shell's all done. Moving right along...\n";` [download] That approach will also work with more recent versions of perl.	[reply] [d/l]

Replies are listed 'Best First'.

Re^5: Multiple commands with one system call
by graff (Chancellor) on Oct 13, 2011 at 19:28 UTC

perl, version 5.005_03 built for sun4-solari

That explains it. Your ancient SunOS system is using an ancient Perl release. The code I posted requires Perl 5.8 or later, due to its use of the "3-argument" form of the open call, which wasn't available in perl 5.5 (which is what you have in this case). Sorry, I just assumed that no one would still be using such an old version of Perl.

To fix that, use the "2-argument" form for the open call -- like this:

#!/usr/bin/perl

use strict;
use warnings;

my @cmd_list = ( 'echo 1', 'echo 2', 'echo 3', 'echo 4' );

$|++;  # turn off buffering

my $shpid = open( my $sh, '|/bin/bash' )
    or die "Can't open a shell process: $!\n";

for my $cmd ( @cmd_list ) {
    print $sh "$cmd\n";
}
print $sh "exit\n";
close $sh;
waitpid( $shpid, 0 );

print "Shell's all done.  Moving right along...\n";
[download]

[reply]
[d/l]