Question

I need to run a command till the system I’m testing fails, or I abort the script. The command I need to run may vary, so I’m taking it as a command-line argument in quotes. But I can’t seem to be able to run a command-line argument using the system command. Here’s what I tried so far (edited my attempt with the script that @Cfreak provided, even with which I see the same issue):

#!/usr/bin/perl


while(1)
{
    print "Iteration #: $count\n";
    $retval = system ($ARGV[1]);
    if( $retval != 0 ) {
        print "System call $ARGV[1] failed with code $retval\n";
    }
    $count++;
}

If I do
./run ls

I see the following prints:

System call  failed with code 65280
Iteration #: 1
System call  failed with code 65280
Iteration #: 2

What am i doing wrong here ?

Answer 1

I believe that you want $ARGV[0] and not $ARGV[1]. You might also want to check to be sure that $ARGV[0] is present.

if( 0 > $#ARGV )
{
  print "No command\n";
}
else
{
  while(1)
  {
    print "$count\n";
    my $ret = system( "ARGV[0]" );
    if( 0 != $ret )
    {
      print "<$ARGV[0] failed with $ret\n";
      exit;
    }
    $count++;
  }
}