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.Dd July 7, 2020 .Dt TIME 1 .Os .Sh NAME .Nm time .Nd time command execution .Sh SYNOPSIS .Nm .Op Fl al .Op Fl h | Fl p .Op Fl o Ar file .Ar utility Op Ar argument ... .Sh DESCRIPTION The .Nm utility executes and times the specified .Ar utility . After the .Ar utility finishes, .Nm writes to the standard error stream, (in seconds): the total time elapsed, the time used to execute the .Ar utility process and the time consumed by system overhead.
p The following options are available: l -tag -width indent t Fl a If the .Fl o flag is used, append to the specified file rather than overwriting it. Otherwise, this option has no effect. t Fl h Print times in a human friendly format. Times are printed in minutes, hours, etc. as appropriate. t Fl l The contents of the .Em rusage structure are printed as well. t Fl o Ar file Write the output to .Ar file instead of stderr. If .Ar file exists and the .Fl a flag is not specified, the file will be overwritten. t Fl p Makes .Nm output POSIX.2 compliant (each time is printed on its own line). .El
p Some shells may provide a builtin .Nm command which is similar or identical to this utility. Consult the .Xr builtin 1 manual page.
p If .Nm receives a .Dv SIGINFO (see the status argument for .Xr stty 1 ) signal, the current time the given command is running will be written to the standard output. .Sh ENVIRONMENT The .Ev PATH environment variable is used to locate the requested .Ar utility if the name contains no .Ql / characters. .Sh EXIT STATUS If .Ar utility could be timed successfully, its exit status is returned. If .Ar utility terminated abnormally, a warning message is output to stderr. If the .Ar utility was found but could not be run, the exit status is 126. If no .Ar utility could be found at all, the exit status is 127. If .Nm encounters any other error, the exit status is between 1 and 125 included. .Sh EXAMPLES Time the execution of .Xr ls 1 on an empty directory: d -literal -offset indent $ /usr/bin/time ls 0.00 real 0.00 user 0.00 sys .Ed
p Time the execution of the .Xr cp 1 command and store the result in the
a times.txt file. Then execute the command again to make a new copy and add the result to the same file: d -literal -offset indent $ /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 .Ed
p The
a times.txt file will contain the times of both commands: d -literal -offset indent $ cat times.txt 0.68 real 0.00 user 0.22 sys 0.67 real 0.00 user 0.21 sys .Ed
p Time the .Xr sleep 1 command and show the results in a human friendly format. Show the contents of the .Em rusage structure too: d -literal -offset indent $ /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 .Ed .Sh SEE ALSO .Xr builtin 1 , .Xr csh 1 , .Xr getrusage 2 , .Xr wait 2 .Sh STANDARDS The .Nm utility is expected to conform to ISO/IEC 9945-2:1993 (``POSIX''). .Sh HISTORY A .Nm utility appeared in .At v3 .