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PMC_CONFIGURE_LOGFILE(3) FreeBSD Library Functions Manual
NAME
pmc_configure_logfile, pmc_flush_logfile, pmc_writelog, pmc_close_logfile
- log file management
LIBRARY
Performance Counters Library (libpmc, -lpmc)
SYNOPSIS
#include <pmc.h>
int
pmc_configure_logfile(int fd);
int
pmc_flush_logfile(void);
int
pmc_writelog(uint32_t userdata);
int
pmc_close_logfile(void);
DESCRIPTION
The functions manage logging of hwpmc(4) events.
Function pmc_configure_logfile() is used to turn on and turn off logging.
If argument fd is a valid file handle returned by a prior call to open(2)
or socket(2) then performance events will be logged to the file
corresponding to the specified handle. If the value of argument fd is -1
then logging will be stopped after any pending data is flushed.
Function pmc_flush_logfile() will force all log data queued inside the
hwpmc(4) driver to be written out.
Function pmc_writelog() will append a log entry containing the value of
argument userdata to the log file.
Function pmc_close_logfile() will flush all pending log data and close
hwpmc(4)'s side of the stream.
RETURN VALUES
Upon successful completion, the value 0 is returned; otherwise the
value -1 is returned and the global variable errno is set to indicate the
error.
ERRORS
A call to pmc_configure_logfile() may fail with the following errors:
[EAGAIN] The hwpmc(4) driver was not able to create a helper
process due to system limits being reached.
[EBUSY] Function pmc_configure_logfile() was called with a log
file already configured.
[EINVAL] Function pmc_configure_logfile() was called with an
argument of -1 without a log file being previously
configured.
file being previously configured.
A call to pmc_writelog() may fail with the following errors:
[EINVAL] Function pmc_writelog() was called without a log file
being previously configured.
[ENOMEM] The system encountered a memory shortage when
servicing this request.
SEE ALSO
pmc(3), hwpmc(4)
FreeBSD 14.0-RELEASE-p11 November 24, 2007 FreeBSD 14.0-RELEASE-p11