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times(3) [osf1 man page]

times(3)						     Library Functions Manual							  times(3)

NAME
times - Gets process and child process times LIBRARY
Standard C Library (libc.so, libc.a) SYNOPSIS
#include <sys/times.h> clock_t times( struct tms *buffer); Programs that are being developed for conformance to the AT&T System V Interface Definition must specify two #include statements, as fol- lows: #include <sys/types.h> #include <sys/times.h> STANDARDS
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. PARAMETERS
Points 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 val- ues 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 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. RETURN VALUES
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. For application portability, the value of CLK_TCK should 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. RELATED INFORMATION
Commands: cc(1) Functions: exec(2), fork(2), getrusage(2), profil(2), stime(3), sysconf(3), time(3), wait(2) Standards: standards(5) delim off times(3)

Check Out this Related Man Page

TIMES(3)						   BSD Library Functions Manual 						  TIMES(3)

NAME
times -- process times LIBRARY
Standard C Library (libc, -lc) SYNOPSIS
#include <sys/times.h> clock_t times(struct tms *tp); DESCRIPTION
This interface is obsoleted by getrusage(2) and gettimeofday(2). The times() function returns the value of time in clock ticks since 0 hours, 0 minutes, 0 seconds, January 1, 1970, Coordinated Universal Time (UTC). The number of clock ticks per second may be determined by calling sysconf(3) with the _SC_CLK_TCK request. It is generally (but not always) between 60 and 1024. Note that at the common rate of 100 ticks per second on many NetBSD ports, and with a 32-bit unsigned clock_t, this value first wrapped in 1971. The times() call also fills in the structure pointed to by tp with time-accounting information. The tms structure is defined as follows: typedef struct { 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_utime s and tms_cutime s of the child processes. tms_cstime The sum of the tms_stimes and tms_cstimes of the child processes. All times are measured in clock ticks, as defined above. Note that at 100 ticks per second, and with a 32-bit unsigned clock_t, the values wrap after 497 days. 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) func- tions 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) STANDARDS
The times() function conforms to ISO/IEC 9945-1:1990 (``POSIX.1''). BSD
June 4, 1993 BSD
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