libtracefs(3)
=============

NAME
----
tracefs_tracers, tracefs_get_clock, tracefs_list_free -
Helper functions for working with trace file system.

SYNOPSIS
--------
[verse]
--
*#include <tracefs.h>*

char pass:[*]pass:[*]*tracefs_tracers*(const char pass:[*]_tracing_dir_);
char pass:[*]*tracefs_get_clock*(struct tracefs_instance pass:[*]_instance_);
void *tracefs_list_free*(char pass:[*]pass:[*]_list_);
--

DESCRIPTION
-----------
Various useful functions for working with trace file system.

The _tracefs_tracers()_ function returns array of strings with the
names of supported tracer plugins, located in the given _tracing_dir_
directory. This could be NULL or the location of the tracefs mount point
for the trace systems of the local machine, or it may be a path to a copy
of the tracefs directory from another machine. The last entry in the array
as a NULL pointer. The array must be freed with _tracefs_list_free()_ API.

The _tracefs_get_clock()_ function returns name of the current trace clock,
used in the given _instance_. If _instance_ is NULL, the clock of the main
trace instance is returned. The returned string must be freed with free().

The _tracefs_list_free()_ function frees an array of strings, returned by
_tracefs_event_systems()_, _tracefs_system_events()_ and _tracefs_tracers()_
APIs.

RETURN VALUE
------------
The _tracefs_tracers()_ returns array of strings. The last element in that
array is a NULL pointer. The array must be freed with _tracefs_list_free()_ API.
In case of an error, NULL is returned.

The _tracefs_get_clock()_ returns string, that must be freed with free(), or NULL
in case of an error.

EXAMPLE
-------
[source,c]
--
#include <tracefs.h>

char **tracers = tracefs_tracers(NULL);

	if (tracers) {
		/* Got tracer plugins from the top trace instance */
		...
		tracefs_list_free(tracers);
	}
....
char *clock = tracefs_get_clock(NULL);

	if (clock) {
		/* Got current trace clock of the top trace instance */
		...
		free(clock);
	}
--
FILES
-----
[verse]
--
*tracefs.h*
	Header file to include in order to have access to the library APIs.
*-ltracefs*
	Linker switch to add when building a program that uses the library.
--

SEE ALSO
--------
_libtracefs(3)_,
_libtraceevent(3)_,
_trace-cmd(1)_

AUTHOR
------
[verse]
--
*Steven Rostedt* <rostedt@goodmis.org>
*Tzvetomir Stoyanov* <tz.stoyanov@gmail.com>
--
REPORTING BUGS
--------------
Report bugs to  <linux-trace-devel@vger.kernel.org>

LICENSE
-------
libtracefs is Free Software licensed under the GNU LGPL 2.1

RESOURCES
---------
https://git.kernel.org/pub/scm/libs/libtrace/libtracefs.git/

COPYING
-------
Copyright \(C) 2020 VMware, Inc. Free use of this software is granted under
the terms of the GNU Public License (GPL).
