time -- time command execution
time [-al] [-h | -p] [-o file] utility [argument ...]
The time utility executes and times the specified utility. After the
utility finishes, time writes to the standard error stream, (in seconds):
the total time elapsed, the time used to execute the utility process and
the time consumed by system overhead.
The following options are available:
-a If the -o flag is used, append to the specified file rather than
overwriting it. Otherwise, this option has no effect.
-h Print times in a human friendly format. Times are printed in
minutes, hours, etc. as appropriate.
-l The contents of the rusage structure are printed as well.
Write the output to file instead of stderr. If file exists and
the -a flag is not specified, the file will be overwritten.
-p Makes time output POSIX.2 compliant (each time is printed on its
Some shells may provide a builtin time command which is similar or identical
to this utility. Consult the builtin(1) manual page.
The PATH environment variable is used to locate the requested utility if
the name contains no `/' characters.
If utility could be timed successfully, its exit status is returned. If
utility terminated abnormally, a warning message is output to stderr. If
the utility was found but could not be run, the exit status is 126. If
no utility could be found at all, the exit status is 127. If time
encounters any other error, the exit status is between 1 and 125
builtin(1), csh(1), getrusage(2), wait(2)
The time utility is expected to conform to ISO/IEC 9945-2:1993
A time utility appeared in Version 3 AT&T UNIX.
FreeBSD 5.2.1 June 6, 1993 FreeBSD 5.2.1 [ Back ]