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                 |  | UGU: Unix Guru Universe - Unix Tip #4480- June 17, 2025
 -  Home : Help
 : Today's Tip Unix Tip #4480- June 17, 2025
 
 
EFFICIENT COMMANDS 
I cringe anytime I see someone code
 inefficiently.  Here are three of the
 most common mistakes, followed by a
 better way to do the same thing.
 
 Bad:    cat somefile | grep something
 Better: grep something somefile
 Why:    You're running one program (grep) instead of two (cat and grep).
 
 Bad:    ps -ef | grep something | grep -v grep
 Better: ps -ef | grep [s]omething
 Why:    You're running two commands (grep) instead of three (ps
 and two greps).
 
 Bad:    cat /dev/null > somefile
 Better: > somefile
 Why:    You're running a command (cat) with I/O redirection,
 instead of just redirection.
 
 Although the bad way will have the
 same result, the good way is far
 faster.  This may seem trivial, but
 the benefits will really show when
 dealing with large files or loops.
 
 Regards.
 
 This tip generously supported by: sec@nbnet.nb.ca
 
 NOTE: All tips provided are USE AT YOUR OWN RISK. Tips are submitted
by various unix admins around the globe. UGU suggest you read and
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