times(2)

NAME

     times - get process and child process times

SYNOPSIS

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

     clock_t times(struct tms *buffer);

DESCRIPTION

     The times() function fills the tms structure pointed  to  by
     buffer  with time-accounting information. The tms structure,
     defined in <sys/times.h>, contains the following members:

     clock_t    tms_utime;
     clock_t    tms_stime;
     clock_t    tms_cutime;
     clock_t    tms_cstime;

     All times are reported in clock ticks.  The  specific  value
     for  a  clock tick is defined by the variable CLK_TCK, found
     in the header <limits.h>.

     The times of a terminated child process are included in  the
     tms_cutime and tms_cstime members of the parent when wait(2)
     or waitpid(2) returns the  process  ID  of  this  terminated
     child.   If a child process has not waited for its children,
     their times will not be included in its times.

     The tms_utime member is the CPU time  used  while  executing
     instructions in the user space of the calling process.

     The tms_stime member is the CPU time used by the  system  on
     behalf of the calling process.

     The tms_cutime member is the sum of the  tms_utime  and  the
     tms_cutime of the child processes.

     The tms_cstime member is the sum of the  tms_stime  and  the
     tms_cstime of the child processes.

RETURN VALUES

     Upon successful completion, times() returns the elapsed real
     time,  in  clock ticks, since an arbitrary point in the past
     (for example, system start-up time).  This  point  does  not
     change  from one invocation of times() within the process to
     another. The return value may overflow the possible range of
     type  clock_t. If times() fails, (clock_t)-1 is returned and
     errno is set to indicate the error.

ERRORS

     The times() function will fail if:

     EFAULT
           The buffer argument points to an illegal address.

ATTRIBUTES

     See attributes(5) for descriptions of the  following  attri-
     butes:

     ____________________________________________________________
    |       ATTRIBUTE TYPE        |       ATTRIBUTE VALUE       |
    |_____________________________|_____________________________|
    | MT-Level                    | Async-Signal-Safe           |
    |_____________________________|_____________________________|

SEE ALSO

     time(1),  timex(1),  exec(2),  fork(2),  time(2),   wait(2),
     waitid(2), waitpid(2), attributes(5)