int clock_getcpuclockid(pid_t pid, clockid_t *clock_id);
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
Upon successful completion, clock_getcpuclockid() shall return
zero; otherwise, an error number shall be returned to
indicate the error.
The clock_getcpuclockid() function shall fail if:
The requesting process does not have permission to access the CPU-time
clock for the process.
The clock_getcpuclockid() function may fail if:
No process can be found corresponding to the process specified by
The following sections are informative.
The clock_getcpuclockid() function is part of the Process CPU-Time
Clocks option and need not be provided on all
clock_getres() , timer_create() , the Base
Definitions volume of IEEE Std 1003.1-2001, <time.h>
Portions of this text are reprinted and reproduced in electronic form
from IEEE Std 1003.1, 2003 Edition, Standard for Information Technology
-- Portable Operating System Interface (POSIX), The Open Group Base
Specifications Issue 6, Copyright (C) 2001-2003 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