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Thread: What does this do in bash: ${pid:-}
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Old 10-12-2008
otheus's Avatar
otheus otheus is offline Forum Staff  
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Join Date: Feb 2007
Location: Innsbruck, Austria
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Granted, null and zero-length are different, but the shell expands them the same way. So really there's no reason for the code as is. It could simply be:

Code:
if [ -z "$pidfile" ] ;then 
  # blah blah
fi

There's actually a simpler way.

Code:
pidfile=${pidfile:-/var/run/${1##*/}.pid}