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TIME(1)			    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  sec-
       onds):  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))  sig-
       nal,  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:

	     $ /usr/bin/time -o	times.txt cp FreeBSD-12.1-RELEASE-amd64-bootonly.iso copy1.iso
	     $ /usr/bin/time -a	-o times.txt cp	FreeBSD-12.1-RELEASE-amd64-bootonly.iso	copy2.iso

       The times.txt file will contain the times of both commands:

	     $ cat times.txt
		     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 for-
       mat.  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	14.3			 July 7, 2020			       TIME(1)

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<https://man.freebsd.org/cgi/man.cgi?query=time&manpath=FreeBSD+14.3-RELEASE+and+Ports>

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