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TIME(1) FreeBSD General Commands Manual TIME(1)
NAME
time - time command execution
SYNOPSIS
time [-al] [-h | -p] [-o file] utility [argument ...]
DESCRIPTION
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.
-o file
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
own line).
Some shells may provide a builtin time command which is similar or
identical to this utility. Consult the builtin(1) manual page.
If time receives a SIGINFO (see the status argument for stty(1)) signal,
the current time the given command is running will be written to the
standard output.
ENVIRONMENT
The PATH environment variable is used to locate the requested utility if
the name contains no `/' characters.
EXIT STATUS
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
included.
EXAMPLES
Time the execution of ls(1) on an empty directory:
$ /usr/bin/time ls
0.00 real 0.00 user 0.00 sys
Time the execution of the cp(1) command and store the result in the
times.txt file. Then execute the command again to make a new copy and
add the result to the same file:
0.68 real 0.00 user 0.22 sys
0.67 real 0.00 user 0.21 sys
Time the sleep(1) command and show the results in a human friendly
format. Show the contents of the rusage structure too:
$ /usr/bin/time -l -h -p sleep 5
real 5.01
user 0.00
sys 0.00
0 maximum resident set size
0 average shared memory size
0 average unshared data size
0 average unshared stack size
80 page reclaims
0 page faults
0 swaps
1 block input operations
0 block output operations
0 messages sent
0 messages received
0 signals received
3 voluntary context switches
0 involuntary context switches
SEE ALSO
builtin(1), csh(1), getrusage(2), wait(2)
STANDARDS
The time utility is expected to conform to ISO/IEC 9945-2:1993
(``POSIX'').
HISTORY
A time utility appeared in Version 3 AT&T UNIX.
FreeBSD 14.0-RELEASE-p11 July 7, 2020 FreeBSD 14.0-RELEASE-p11