Name
:
Synopsis
:
Null command. Returns an exit status of 0. Sometimes used as the first character in a file to denote a bash script. Shell variables can be placed after the :
to expand them to their values.
Example
To check whether someone is logged in:
if who | grep -w $1 > /dev/null
then : # do nothing
# if pattern is found
else echo "User $1 is not logged in"
fi
Get Mac OS X Tiger in a Nutshell now with the O’Reilly learning platform.
O’Reilly members experience books, live events, courses curated by job role, and more from O’Reilly and nearly 200 top publishers.