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.

     [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)

FreeBSD 13.1-RELEASE-p6        November 24, 2007       FreeBSD 13.1-RELEASE-p6