PMC_CONFIGURE_LOGFILE(3)

NAME
pmc_configure_logfile, pmc_flush_logfile, pmc_writelog - log file management

LIBRARY
libpmc

SYNOPSIS
#include <pmc.h>
int
pmc_configure_logfile(int fd);
int
pmc_flush_logfile(void);
int
pmc_writelog(uint32_t userdata);

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.

RETURN VALUES

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.

[ENOMEM]
    The system encountered a memory shortage when servicing this request.

A call to pmc_flush_logfile() may fail with the following errors:

[EINVAL]
    Function pmc_flush_logfile() was called without a log 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)