As with system and exec, 
open (my $ARTICLE, "-|", $shell_command)

[download]
is short for 
open (my $ARTICLE, "-|", "cmd", "/x", "/c", $shell_command)

[download]

open successfully executed cmd as requested. No error occurred, so it returned the pid of the child.

Presumably, cmd will return an error for being unable to execute ceasar. Of this you will be notified when you close the handle. It will return false with a true value for $? >> 8.

In reply to Re: Capturing errors from 3-arg pipe open in ActivePerl 5.020 by ikegami
in thread [SOLVED] Capturing errors from 3-arg pipe open in ActivePerl 5.020 by ateague

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