NAME
time
—
time command execution
SYNOPSIS
time |
[-lp ] utility
[argument ...] |
DESCRIPTION
time
executes and times
utility with optional arguments.
After the utility finishes,
time
writes the total time elapsed, the time
consumed by system overhead, and the time used to execute
utility to the standard error stream. Times are
reported in seconds.
The options are as follows:
-l
- The contents of the rusage structure are printed.
-p
- The output is formatted as specified by IEEE Std 1003.2-1992 (“POSIX.2”).
FILES
- /usr/include/sys/resource.h
EXIT STATUS
The time
utility exits with one of the
following values:
- 1-125
- An error occurred in the
time
utility. - 126
- The utility was found but could not be invoked.
- 127
- The utility could not be found.
Otherwise, the exit status of time
shall
be that of utility.
SEE ALSO
STANDARDS
The time
utility is compliant with the
IEEE Std 1003.1-2008 (“POSIX.1”)
specification.
The flag [-l
] is an extension to that
specification.
time
also exists as a built-in to
csh(1) and ksh(1), though with a different syntax.
HISTORY
A time
command appeared in
Version 3 AT&T UNIX.
BUGS
The granularity of seconds on microprocessors is crude and can result in times being reported for CPU usage which are too large by a second.