NAME
times
—
process times
LIBRARY
library “libc”
SYNOPSIS
#include
<sys/times.h>
clock_t
times
(struct
tms *tp);
DESCRIPTION
The
times
()
function returns the value of time in CLK_TCK
's of a
second since the system startup time. The current value of
CLK_TCK
, the frequency of the statistics clock in
ticks per second, may be obtained through the
sysconf(3) interface.
It also fills in the structure pointed to by tp with time-accounting information.
The tms structure is defined as follows:
struct tms { clock_t tms_utime; clock_t tms_stime; clock_t tms_cutime; clock_t tms_cstime; };
The elements of this structure are defined as follows:
- tms_utime
- The CPU time charged for the execution of user instructions.
- tms_stime
- The CPU time charged for execution by the system on behalf of the process.
- tms_cutime
- The sum of the tms_utimes and tms_cutimes of the child processes.
- tms_cstime
- The sum of the tms_stimes and tms_cstimes of the child processes.
All times are in CLK_TCK
's of a
second.
The times of a terminated child process are included
in the tms_cutime and tms_cstime
elements of the parent when one of the
wait(2) functions returns the process ID of the terminated child to
the parent. If an error occurs,
times
()
returns the value ((clock_t)-1), and sets
errno to indicate the error.
ERRORS
The times
() function may fail and set the
global variable errno for any of the errors specified
for the library routines
getrusage(2) and
gettimeofday(2).
SEE ALSO
time(1), getrusage(2), gettimeofday(2), wait(2), sysconf(3), clocks(7)
STANDARDS
The times
() function conforms to
IEEE Std 1003.1-1988 (“POSIX.1”).