Standard C Library (libc.so, libc.a)
struct tms *buffer);
Programs that are being developed for conformance to the AT&T System V Interface Definition must specify two #include statements, as follows:
#include <sys/types.h> #include <sys/times.h>
Interfaces documented on this reference page conform to industry standards as follows:
times(): XPG4, XPG4-UNIX
Refer to the standards(5) reference page for more information about industry standards and associated tags.
The times of a terminated child process are included in the tms_cutime and tms_cstime elements of the parent process when a wait 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: User time. The CPU time charged while executing user instructions of the calling process. System time. The CPU time charged during system execution on behalf of the calling process. User time, children. The sum of the tms_utime and the tms_cutime times of the child processes. 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.
Upon successful completion, the times() function returns the elapsed real time since an arbitrary reference time in the past (for example, system start-up time). The reference time does not change from one invocation of times() within the process to another. The elapsed 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(3)).
The return value may overflow the possible range of type clock_t values. When the times() function fails, a value of (clock_t)-1 is returned.
Functions: exec(2), fork(2), getrusage(2), profil(2), stime(3), sysconf(3), time(3), wait(2)
Standards: standards(5) delim off