NAME

time - time command execution

SYNOPSIS

time [-clp] utility [argument ...]

DESCRIPTION

The time utility executes and times utility. 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.

Available options:

-c
Displays the default csh(1) summary format.

-l
Lists resource utilization information. The contents of the utility process' rusage structure are printed, see below.

-p
The output is formatted as specified by IEEE Std 1003.2-1992 (``POSIX.2'') .

Some shells, such as csh(1) and ksh(1), have their own and syntactically different builtin version of . The utility described here is available as /usr/bin/time to users of these shells.

Resource Utilization

If the -l option is given, the following resource usage informations are displayed in addition to the timing information:
maximum resident set size
average shared memory size
average unshared data size
average unshared stack size
page reclaims
page faults
swaps
block input operations
block output operations
messages sent
messages received
signals received
voluntary context switches
involuntary context switches

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 will be that of utility.

FILES

<sys/resource.h>

SEE ALSO

csh(1), ksh(1), getrusage(2)

STANDARDS

The time utility conforms to IEEE Std 1003.2-1992 (``POSIX.2'') .

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.