+++ /dev/null
-.\" Copyright (c) 2009 Linux Foundation, written by Michael Kerrisk
-.\" <mtk.manpages@gmail.com>
-.\"
-.\" %%%LICENSE_START(VERBATIM)
-.\" Permission is granted to make and distribute verbatim copies of this
-.\" manual provided the copyright notice and this permission notice are
-.\" preserved on all copies.
-.\"
-.\" Permission is granted to copy and distribute modified versions of this
-.\" manual under the conditions for verbatim copying, provided that the
-.\" entire resulting derived work is distributed under the terms of a
-.\" permission notice identical to this one.
-.\"
-.\" Since the Linux kernel and libraries are constantly changing, this
-.\" manual page may be incorrect or out-of-date. The author(s) assume no
-.\" responsibility for errors or omissions, or for damages resulting from
-.\" the use of the information contained herein. The author(s) may not
-.\" have taken the same level of care in the production of this manual,
-.\" which is licensed free of charge, as they might when working
-.\" professionally.
-.\"
-.\" Formatted or processed versions of this manual, if unaccompanied by
-.\" the source, must acknowledge the copyright and authors of this work.
-.\" %%%LICENSE_END
-.\"
-.TH PTHREAD_GETCPUCLOCKID 3 2014-05-23 "Linux" "Linux Programmer's Manual"
-.SH NAME
-pthread_getcpuclockid \- retrieve ID of a thread's CPU time clock
-.SH SYNOPSIS
-.nf
-.B #include <pthread.h>
-.B #include <time.h>
-
-.BI "int pthread_getcpuclockid(pthread_t " thread ", clockid_t *" clock_id );
-.sp
-Compile and link with \fI\-pthread\fP.
-.fi
-.SH DESCRIPTION
-The
-.BR pthread_getcpuclockid ()
-function returns the clock ID for the CPU time clock of the thread
-.IR thread .
-.\" The clockid is constructed as follows:
-.\" *clockid = CLOCK_THREAD_CPUTIME_ID | (pd->tid << CLOCK_IDFIELD_SIZE)
-.\" where CLOCK_IDFIELD_SIZE is 3.
-.SH RETURN VALUE
-On success, this function returns 0;
-on error, it returns a nonzero error number.
-.SH ERRORS
-.TP
-.B ENOENT
-.\" CLOCK_THREAD_CPUTIME_ID not defined
-Per-thread CPU time clocks are not supported by the system.
-.\"
-.\" Looking at nptl/pthread_getcpuclockid.c an ERANGE error would
-.\" be possible if kernel thread IDs took more than 29 bits (which
-.\" they currently cannot).
-.TP
-.B ESRCH
-No thread with the ID
-.I thread
-could be found.
-.SH VERSIONS
-This function is available in glibc since version 2.2.
-.SH ATTRIBUTES
-.SS Multithreading (see pthreads(7))
-The
-.BR pthread_getcpuclockid ()
-function is thread-safe.
-.SH CONFORMING TO
-POSIX.1-2001.
-.SH NOTES
-When
-.I thread
-refers to the calling thread,
-this function returns an identifier that refers to the same clock
-manipulated by
-.BR clock_gettime (2)
-and
-.BR clock_settime (2)
-when given the clock ID
-.BR CLOCK_THREAD_CPUTIME_ID .
-.SH EXAMPLE
-The program below creates a thread and then uses
-.BR clock_gettime (2)
-to retrieve the total process CPU time,
-and the per-thread CPU time consumed by the two threads.
-The following shell session shows an example run:
-
-.in +4n
-.nf
-$ \fB./a.out\fP
-Main thread sleeping
-Subthread starting infinite loop
-Main thread consuming some CPU time...
-Process total CPU time: 1.368
-Main thread CPU time: 0.376
-Subthread CPU time: 0.992
-.fi
-.in
-.SS Program source
-\&
-.nf
-/* Link with "\-lrt" */
-
-#include <time.h>
-#include <stdio.h>
-#include <stdlib.h>
-#include <unistd.h>
-#include <pthread.h>
-#include <string.h>
-#include <errno.h>
-
-#define handle_error(msg) \\
- do { perror(msg); exit(EXIT_FAILURE); } while (0)
-
-#define handle_error_en(en, msg) \\
- do { errno = en; perror(msg); exit(EXIT_FAILURE); } while (0)
-
-static void *
-thread_start(void *arg)
-{
- printf("Subthread starting infinite loop\\n");
- for (;;)
- continue;
-}
-
-static void
-pclock(char *msg, clockid_t cid)
-{
- struct timespec ts;
-
- printf("%s", msg);
- if (clock_gettime(cid, &ts) == \-1)
- handle_error("clock_gettime");
- printf("%4ld.%03ld\\n", ts.tv_sec, ts.tv_nsec / 1000000);
-}
-
-int
-main(int argc, char *argv[])
-{
- pthread_t thread;
- clockid_t cid;
- int j, s;
-
- s = pthread_create(&thread, NULL, thread_start, NULL);
- if (s != 0)
- handle_error_en(s, "pthread_create");
-
- printf("Main thread sleeping\\n");
- sleep(1);
-
- printf("Main thread consuming some CPU time...\\n");
- for (j = 0; j < 2000000; j++)
- getppid();
-
- pclock("Process total CPU time: ", CLOCK_PROCESS_CPUTIME_ID);
-
- s = pthread_getcpuclockid(pthread_self(), &cid);
- if (s != 0)
- handle_error_en(s, "pthread_getcpuclockid");
- pclock("Main thread CPU time: ", cid);
-
- /* The preceding 4 lines of code could have been replaced by:
- pclock("Main thread CPU time: ", CLOCK_THREAD_CPUTIME_ID); */
-
- s = pthread_getcpuclockid(thread, &cid);
- if (s != 0)
- handle_error_en(s, "pthread_getcpuclockid");
- pclock("Subthread CPU time: 1 ", cid);
-
- exit(EXIT_SUCCESS); /* Terminates both threads */
-}
-.fi
-.SH SEE ALSO
-.BR clock_gettime (2),
-.BR clock_settime (2),
-.BR timer_create (2),
-.BR clock_getcpuclockid (3),
-.BR pthread_self (3),
-.BR pthreads (7),
-.BR time (7)
-.SH COLOPHON
-This page is part of release 3.79 of the Linux
-.I man-pages
-project.
-A description of the project,
-information about reporting bugs,
-and the latest version of this page,
-can be found at
-\%http://www.kernel.org/doc/man\-pages/.
OSDN Git Service
