clock_getcpuclockid - Man Page
access a process CPU-time clock (ADVANCED REALTIME)
Prolog
This manual page is part of the POSIX Programmer's Manual. The Linux implementation of this interface may differ (consult the corresponding Linux manual page for details of Linux behavior), or the interface may not be implemented on Linux.
Synopsis
#include <time.h> int clock_getcpuclockid(pid_t pid, clockid_t *clock_id);
Description
The clock_getcpuclockid() function shall return the clock ID of the CPU-time clock of the process specified by pid. If the process described by pid exists and the calling process has permission, the clock ID of this clock shall be returned in clock_id.
If pid is zero, the clock_getcpuclockid() function shall return the clock ID of the CPU-time clock of the process making the call, in clock_id.
The conditions under which one process has permission to obtain the CPU-time clock ID of other processes are implementation-defined.
Return Value
Upon successful completion, clock_getcpuclockid() shall return zero; otherwise, an error number shall be returned to indicate the error.
Errors
The clock_getcpuclockid() function shall fail if:
- EPERM
The requesting process does not have permission to access the CPU-time clock for the process.
The clock_getcpuclockid() function may fail if:
- ESRCH
No process can be found corresponding to the process specified by pid.
The following sections are informative.
Examples
None.
Application Usage
The clock_getcpuclockid() function is part of the Process CPU-Time Clocks option and need not be provided on all implementations.
Rationale
None.
Future Directions
None.
See Also
clock_getres(), timer_create()
The Base Definitions volume of POSIX.1-2017, <time.h>
Copyright
Portions of this text are reprinted and reproduced in electronic form from IEEE Std 1003.1-2017, Standard for Information Technology -- Portable Operating System Interface (POSIX), The Open Group Base Specifications Issue 7, 2018 Edition, Copyright (C) 2018 by the Institute of Electrical and Electronics Engineers, Inc and The Open Group. In the event of any discrepancy between this version and the original IEEE and The Open Group Standard, the original IEEE and The Open Group Standard is the referee document. The original Standard can be obtained online at http://www.opengroup.org/unix/online.html .
Any typographical or formatting errors that appear in this page are most likely to have been introduced during the conversion of the source files to man page format. To report such errors, see https://www.kernel.org/doc/man-pages/reporting_bugs.html .
Referenced By
clock_getres(3p), pthread_getcpuclockid(3p), time.h(0p).