NAME

times − Gets process and child process times

LIBRARY

Standard C Library (libc.a)

SYNOPSIS

#include <sys/types.h>

#include <sys/times.h>

clock_t times(

struct tms ∗buffer) ;

PARAMETERS

bufferPoints to type tms structure space where system time information is stored. 

DESCRIPTION

The times() function fills the type tms structure space pointed to by the buffer parameter with time-accounting information.  All time values reported by this function are in hardware-dependent clock ticks. 

The times of a terminated child process are included in the tms_cutime and tms_cstime elements of the parent process when a wait() or waitpid() function returns the process ID of that terminated child. 

The tms structure, which  is defined in the sys/times.h header file, contains the following members:

time_t   tms_utime
User time. The CPU time charged while executing user instructions of the calling process.

time_t   tms_stime
System time. The CPU time charged during system execution on behalf of the calling process.

time_t   tms_cutime
User time, children. The sum of the tms_utime and the tms_cutime times of the child processes. 

time_t   tms_cstime
System time, children. The sum of the tms_stime and the tms_cstime times of the child processes. 

When a child process does not wait for its children, its child-process times are not included in its times. 

This information comes from the calling process and each of its terminated child processes for which a wait() function has been executed. 

NOTES

AES Support Level:  Full use

RETURN VALUES

Upon successful completion, the times() function returns the elapsed real time in clock ticks since an arbitrary reference time in the past (for example, system start-up time). This reference time does not change from one times() function to another. The return value may overflow the possible range of type clock_t values. When the times() function fails, a value of -1 is returned. 

RELATED INFORMATION

Functions: exec(2), fork(2), getrusage(2), profil(2), stime(3), sysconf(3), time(3), wait(2)

Commands: cc(1)