V10/man/man1/time.1

.TH TIME 1
.CT 1 proc_man time_man debug_tune
.SH NAME
time \- time a command
.SH SYNOPSIS
.B time
[
.B -usrtdmfio
]
[
.B -v
]
.I command
.SH DESCRIPTION
The
given command is executed; after it is complete,
.I time
reports statistics about the program on its standard error output.
The statistics printed are controlled by the option string;
the default is
.BR -usr ;
.B -v
reports everything.
The statistics are:
.TP
.B u
User cpu time consumed by the command
.TP
.B s
System cpu time attributed to the command
.TP
.B r
Real (clock) time taken by the command
.TP
.B t
Average resident text size, in Kb.
.TP
.B d
Average resident data size, in Kb.
.TP
.B m
Maximum total resident size, in Kb.
.TP
.B f
Number of page faults resulting in disk I/O.
.TP
.B i
Number of disk blocks read.
.TP
.B o
Number of disk blocks written.
.PP
After the statistics,
.I time
prints a tab and the command, up to the fifth argument.
Times are reported in seconds.
The numbers are the sum of those for
.I command
and any children it spawns and waits for.
.SH "SEE ALSO"
.IR lcomp (1),
.IR prof (1)
.SH BUGS
Elapsed time is accurate to the second,
while the CPU times are measured
to 1/60 second.
Thus the sum of the CPU times can be up to a second larger
than the elapsed time.