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times(3)
NAME
  times - Get process and child process times

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 follows:

       #include <sys/types.h>
       #include <sys/times.h>

LIBRARY
  Standard C Library (libc)

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
  buffer
      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 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 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:

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

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

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

  clock_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.

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.

SEE ALSO
  Commands: cc(1)

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

  Standards: standards(5)

Index for Section 3

Alphabetical listing for T

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