FAQ 8.24 Why can't I get the output of a command with system()?

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8.24: Why can't I get the output of a command with system()?

You're confusing the purpose of system() and backticks (``). system()
runs a command and returns exit status information (as a 16 bit value:
the low 7 bits are the signal the process died from, if any, and the
high 8 bits are the actual exit value). Backticks (``) run a command and
return what it sent to STDOUT.

$exit_status = system("mail-users");
$output_string = `ls`;

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