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Whenever I try to use options with the time command, such as format (-f, --FORMAT), I get the following error:

bash: -f: command not found

How do I use options with time?

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up vote 10 down vote accepted

You are invoking the bash's built-in version of time, which has slightly different behavior and options – described in bash's manual as well as help time.

Use command time ... to bypass the built-in and execute the external command; or run /usr/bin/time ... directly.

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This fixed my issue. I was unaware there was a difference between the man page and bashes version on any of the commands, add that to the things I learned today. – Wipqozn Mar 8 '12 at 16:28
If it's all settled, click the check mark next to the answer to accept this answer. – Doug Harris Mar 8 '12 at 16:30
Bash's built-in type function will show which you'll run -- e.g. type time. Add the -a option to show all -- type -a time – Doug Harris Mar 8 '12 at 16:32
@DougHarris I know how to accept an answer, but there is a 15 minute delay between asking and when you can accept. – Wipqozn Mar 8 '12 at 16:33
Ah, sorry. The downside to getting help so quickly :-) – Doug Harris Mar 8 '12 at 16:34

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