The system function doc it contains some chunks of code that you could put directly into a subroutine:

                   @args = ("command", "arg1", "arg2");
                   system(@args) == 0
                        or die "system @args failed: $?"

               You can check all the failure possibilities by inspecti
+ng $?
               like this:

                   if ($? == -1) {
                       print "failed to execute: $!\n";
                   }
                   elsif ($? & 127) {
                       printf "child died with signal %d, %s coredump\
+n",
                           ($? & 127),  ($? & 128) ? 'with' : 'without
+';
                   }
                   else {
                       printf "child exited with value %d\n", $? >> 8;
                   }

[download]

Update: I adapted it for a program of mine this way:

#!/usr/bin/perl

use strict ;
use warnings ;

use Carp ;

# some code here

sub check_cmd {
  my %parms = @_ ;

  croak "No commands" unless
    exists $parms{cmd} and ref($parms{cmd}) eq 'ARRAY' ;

  my @cmd = @{$parms{cmd}} ;

  $parms{onerror} = 'croak' unless exists $parms{onerror} ;
  $parms{onerror} =  lc $parms{onerror} ;
  $parms{onerror} = 'croak' unless $parms{onerror} =~ /^(croak|carp|no
+ne)$/ ;

  $parms{errormsg} = "@cmd failed" unless exists $parms{errormsg} ;

  my $result = system(@cmd) ;
  unless ($result == 0) {
    print STDERR $parms{errormsg} ;
    croak report_error($?,$!) if $parms{onerror} eq 'croak' ;
    if ($parms{onerror} eq 'carp') {
      carp  report_error($?,$!) ;
      print STDERR "Press ENTER" ;
      scalar <STDIN> ;
    }
  }

  return $result >> 8 ; # exit value
}

sub report_error {
  my ($syserr,$message) = @_ ;
  my $signal    = $syserr & 127 ;
  my $exitvalue = $syserr >> 8 ;
  my $error ;

  if ($syserr == -1) {
    $error = "failed to execute: $message" ;
  } elsif ($signal) {
    $error = "program died with signal $signal" ;
  }

  return $error ;
}

[download]

The subroutine was called like this:

    $ret = check_cmd(cmd      => [$config{cvs_command},'login'],
                     onerror  => 'none',
                     errormsg => "cvs login failed") ;

    unless ($ret == 0) {
      # do something...
    }

[download]

I hope this helps a bit

Ciao!
--bronto

The very nature of Perl to be like natural language--inconsistant and full of dwim and special cases--makes it impossible to know it all without simply memorizing the documentation (which is not complete or totally correct anyway).
--John M. Dlugosz

In reply to Re: shell within perl by bronto
in thread shell within perl by Anonymous Monk

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post, it's "PerlMonks-approved HTML":


  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.