CPC_ACCESS(3CPC)CPC_ACCESS(3CPC)NAMEcpc_access - test access CPU performance counters
SYNOPSIS
cc [ flag... ] file... −lcpc [ library... ]
#include <libcpc.h>
int cpc_access(void);
DESCRIPTION
Access to CPU performance counters is possible only on systems where
the appropriate hardware exists and is correctly configured. The
cpc_access() function must be used to determine if the hardware exists
and is accessible on the platform before any of the interfaces that use
the counters are invoked.
When the hardware is available, access to the per-process counters is
always allowed to the process itself, and allowed to other processes
mediated using the existing security mechanisms of /proc.
RETURN VALUES
Upon successful completion, cpc_access() returns 0. Otherwise, it
returns −1 and sets errno to indicate the error.
By default, two common errno values are decoded and cause the library
to print an error message using its reporting mechanism. See cpc_seter‐
rfn(3CPC) for a description of how this behavior can be modified.
ERRORS
The cpc_access() function will fail if:
EAGAIN
Another process may be sampling system-wide CPU statistics.
ENOSYS
CPU performance counters are inaccessible on this machine.
This error can occur when the machine supports CPU perfor‐
mance counters, but some software components are missing.
Check to see that all CPU Performance Counter packages have
been correctly installed.
ATTRIBUTES
See attributes(5) for descriptions of the following attributes:
┌────────────────────┬─────────────────┐
│ATTRIBUTE TYPE │ ATTRIBUTE VALUE │
├────────────────────┼─────────────────┤
│MT-Level │ MT-Safe │
├────────────────────┼─────────────────┤
│Interface Stability │ Obsolete │
└────────────────────┴─────────────────┘
SEE ALSOcpc(3CPC), cpc_open(3CPC), cpc_seterrfn(3CPC), libcpc(3LIB), proc(4),
attributes(5)NOTES
The cpc_access() function exists for binary compatibility only. Source
containing this function will not compile. This function is obsolete
and might be removed in a future release. Applications should use
cpc_open(3CPC) instead.
Mar 28, 2005 CPC_ACCESS(3CPC)