times(2) times(2)
NAME [Toc] [Back]
times - get process and child process times
SYNOPSIS [Toc] [Back]
#include <sys/times.h>
clock_t times(struct tms *buffer);
DESCRIPTION [Toc] [Back]
times() fills the structure pointed to by buffer with time-accounting
information. The structure defined in <sys/times.h> is as follows:
struct tms {
clock_t tms_utime; /* user time */
clock_t tms_stime; /* system time */"
clock_t tms_cutime; /* user time, children */
clock_t tms_cstime; /* system time, children */
};
This information comes from the calling process and each of its
terminated child processes for which it has executed a wait(),
wait3(), or waitpid(). The times are in units of 1/CLK_TCK seconds,
where CLK_TCK is processor dependent The value of CLK_TCK can be
queried using the sysconf() function (see sysconf(2)).
tms_utime is the CPU time used while executing instructions in the
user space of the calling process.
tms_stime is the CPU time used by the system on behalf of the calling
process.
tms_cutime is the sum of the tms_utimes and tms_cutimes of the child
processes.
tms_cstime is the sum of the tms_stimes and tms_cstimes of the child
processes.
RETURN VALUE [Toc] [Back]
Upon successful completion, times() returns the elapsed real time, in
units of 1/CLK_TCK of a second, since an arbitrary point in the past
(such as system start-up time). This point does not change from one
invocation of times() to another. If times() fails, -1 is returned
and errno is set to indicate the error.
Remarks [Toc] [Back]
times() has a granularity of one tick. Processes which run less than
one tick may not register any value.
ERRORS [Toc] [Back]
[EFAULT] times() fails if buffer points to an illegal address.
The reliable detection of this error is implementation
Hewlett-Packard Company - 1 - HP-UX 11i Version 2: August 2003
times(2) times(2)
dependent.
SEE ALSO [Toc] [Back]
time(1), gettimeofday(2), exec(2), fork(2), sysconf(2), time(2),
wait(2).
WARNINGS [Toc] [Back]
Not all CPU time expended by system processes on behalf of a user
process is counted in the system CPU time for that process.
STANDARDS CONFORMANCE [Toc] [Back]
times(): AES, SVID2, SVID3, XPG2, XPG3, XPG4, FIPS 151-2, POSIX.1
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