NAME

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

SYNOPSIS

       #include <tracefs.h>

       char **tracefs_tracers(const char *tracing_dir);
       char *tracefs_get_clock(struct tracefs_instance *instance);
       void tracefs_list_free(char **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

           #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

           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

           Steven Rostedt <rostedt@goodmis.org[1]>
           Tzvetomir Stoyanov <tz.stoyanov@gmail.com[2]>

REPORTING BUGS

       Report bugs to <linux-trace-devel@vger.kernel.org[3]>

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).

NOTES

        1. rostedt@goodmis.org
           mailto:rostedt@goodmis.org

        2. tz.stoyanov@gmail.com
           mailto:tz.stoyanov@gmail.com

        3. linux-trace-devel@vger.kernel.org
           mailto:linux-trace-devel@vger.kernel.org

libtracefs 1.2.5                                   08/29/2021                                      LIBTRACEFS(3)