I am trying to write a simple helper script that will call three external programs multiple times (based on some parsed data). My problem is that Perl's system() call is returning before the command finishes. I have looked at the program I'm calling and it is actually a Perl script that calls additional programs (but this script can NOT be changed). The system() call returns while these programs execute in the background. The called program prints a final status message that I thought I could capture with my script to ensure that the system() call completed. Below is the snippet of the called program (that I can't edit) showing the final status message: 
  if ($exit_status != 0) {
    print("-F-Job completed abnormally.(status = $exit_status)\n");
  } else {
    print("-I-Job completed successfully.\n");
  }

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As you can see, this is a simple print statement. After various attempts I am unable to capture this output. Below is my code snippet intended to capture STDOUT and STDERR and print each line. In my final program I will change this code to wait until I see either the success or failure message. 
  $command = "program_to_run $opt{c} -f test";
  # print "$command\n";
  open(RUN, "$command 2>&1|");
  while (<RUN>) {
    print "$_\n";
    next;
  }
  close(RUN);
exit 0;

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When I uncomment the print $command line it prints the correct system command. However, the print statements from that system command are not being captured. Am I doing something wrong? Thanks in advance for any tips you can provide. Greg

In reply to Unable to capture STDOUT from system command by Greg_R

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