cputime(2) [plan9 man page]

CPUTIME(2)							System Calls Manual							CPUTIME(2)

NAME

       cputime, times - cpu time in this process and children

SYNOPSIS

       #include <u.h>
       #include <libc.h>

       int    times(long t[4])

       double cputime(void)

DESCRIPTION

       If  t  is  non-null,  times fills it in with the number of milliseconds spent in user code, system calls, child processes in user code, and
       child processes in system calls.  Cputime returns the sum of those same times, converted to seconds.  Times returns the real time, in  mil-
       liseconds used by the process so far.

       These functions read /dev/cputime, opening that file when time is first called.

SOURCE

       /sys/src/libc/9sys

SEE ALSO

       cons(3)

																	CPUTIME(2)

times(2)							   System Calls 							  times(2)

NAME

       times - get process and child process times

SYNOPSIS

       #include <sys/times.h>
       #include <limits.h>

       clock_t times(struct tms *buffer);

DESCRIPTION

       The  times()  function  fills  the  tms	structure  pointed  to	by  buffer with time-accounting information. The tms structure, defined in
       <sys/times.h>, contains the following members:

	 clock_t    tms_utime;
	 clock_t    tms_stime;
	 clock_t    tms_cutime;
	 clock_t    tms_cstime;

       All times are reported in clock ticks. The specific value for a clock tick is defined by the variable CLK_TCK, found in	the  header  <lim-
       its.h>.

       The  times  of  a terminated child process are included in the tms_cutime and tms_cstime members of the parent when wait(3C) or waitpid(3C)
       returns the process ID of this terminated child.  If a child process has not waited for its children, their times will not be  included	in
       its times.

       The tms_utime member is the CPU time used while executing instructions in the user space of the calling process.

       The tms_stime member is the CPU time used by the system on behalf of the calling process.

       The tms_cutime member is the sum of the tms_utime and the tms_cutime of the child processes.

       The tms_cstime member is the sum of the tms_stime and the tms_cstime of the child processes.

RETURN VALUES

       Upon  successful completion, times() returns the elapsed real time, in clock ticks, since an arbitrary point in the past (for example, sys-
       tem start-up time). This point does not change from one invocation of times() within the process to another. The return value may  overflow
       the possible range of type clock_t. If times() fails, (clock_t)-1 is returned and errno is set to indicate the error.

ERRORS

       The times() function will fail if:

       EFAULT	 The buffer argument points to an illegal address.

ATTRIBUTES

       See attributes(5) for descriptions of the following attributes:

       +-----------------------------+-----------------------------+
       |      ATTRIBUTE TYPE	     |	    ATTRIBUTE VALUE	   |
       +-----------------------------+-----------------------------+
       |Interface Stability	     |Standard			   |
       +-----------------------------+-----------------------------+
       |MT-Level		     |Async-Signal-Safe 	   |
       +-----------------------------+-----------------------------+

SEE ALSO

       time(1), timex(1), exec(2), fork(2), time(2), waitid(2), wait(3C), waitpid(3C), attributes(5), standards(5)

SunOS 5.11							    14 May 1997 							  times(2)