times.2

Unix操作系统minix 2.0源码

.\" Copyright (c) 1980 Regents of the University of California.
.\" All rights reserved.  The Berkeley software License Agreement
.\" specifies the terms and conditions for redistribution.
.\"
.\"	@(#)times.3c	6.1 (Berkeley) 5/9/85
.\"
.TH TIMES 2 "May 9, 1985"
.UC 4
.SH NAME
times \- get process times
.SH SYNOPSIS
.nf
.ft B
#include <sys/types.h>
#include <sys/times.h>
#include <time.h>

int times(struct tms *\fIbuffer\fP)
.fi
.SH DESCRIPTION
.B Times
returns time-accounting information
for the current process
and for the terminated child processes
of the current process.
All times are in 1/CLOCKS_PER_SEC seconds.
.PP
This is the structure returned by
.BR times :
.PP
.RS
.nf
.ta +0.4i +0.8i +1.2i
struct tms {
	clock_t	tms_utime;	/* user time for this process */
	clock_t	tms_stime;	/* system time for this process */
	clock_t	tms_cutime;	/* children's user time */
	clock_t	tms_cstime;	/* children's system time */
};
.fi
.RE
.PP
The user time is the number of clock ticks used by a process on
its own computations.  The system time is the number of clock ticks
spent inside the kernel on behalf of a process.  This does not
include time spent waiting for I/O to happen, only actual CPU
instruction times.
.PP
The children times are the sum
of the children's process times and
their children's times.
.SH RETURN
.B Times
returns 0 on success, otherwise \-1 with the error code stored into the
global variable
.BR errno .
.SH ERRORS
The following error code may be set in
.BR errno :
.TP 15
[EFAULT]
The address specified by the
.I buffer
parameter is not in a valid part of the process address space.
.SH "SEE ALSO"
.BR time (1),
.BR wait (2),
.BR time (2).