xref: /freebsd/usr.bin/time/time.1 (revision 03a2224899c8c0329e0b49c19000d88f940617d5)

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.\"     @(#)time.1	8.1 (Berkeley) 6/6/93
.\"
.Dd June 6, 1993
.Dt TIME 1
.Os BSD 4
.Sh NAME
.Nm time
.Nd time command execution
.Sh SYNOPSIS
.Nm
.Op Fl a Ar file
.Op Fl f Ar file
.Op Fl l
.Ar command
.Sh DESCRIPTION
The
.Nm
utility
executes and
times
.Ar command
by initiating a timer and passing the
.Ar command
to the
shell.
After the
.Ar command
finishes,
.Nm
writes to the standard error stream,
(in seconds):
the total time elapsed,
time consumed by system overhead,
and the time used to execute the
.Ar command
process.
.Pp
Available options:
.Bl -tag -width Ds
.It Fl a Ar file
Append the output of
.Nm
to
.Ar file
instead of writing to stderr.
.It Fl f Ar file
Write the output to
.Ar file
instead of stderr.  If
.Ar file
exists, then
.Nm
will overwrite the file if premissions permit such an operation.
The output can be sent to stdout by giving
a file name
.Do
-
.Dc
to the
.Fl f
option.
.It Fl l
The contents of the
.Em rusage
structure are printed as well.
.El
.Pp
The
.Xr csh 1
has its own and syntactically different builtin version of
.Nm time .
The command described here
is available as
.Pa /usr/bin/time
to
.Xr csh
users.
.Sh BUGS
The granularity of seconds on micro processors is crude and
can result in times being reported for CPU usage which are too large by
a second.
.Sh SEE ALSO
.Xr csh 1 ,
.Xr getrusage 2 ,
.Xr wait 2
.Sh HISTORY
A
.Nm
command appeared in
.At v6 .