NAME

       tracefs_option_enable, tracefs_option_disable, tracefs_option_name - Various trace option
       functions.

SYNOPSIS

       #include <tracefs.h>

       int tracefs_option_enable(struct tracefs_instance *instance, enum tracefs_option_id id);
       int tracefs_option_disable(struct tracefs_instance *instance, enum tracefs_option_id id);
       const char *tracefs_option_name(enum tracefs_option_id id);

DESCRIPTION

       This set of APIs can be used to enable and disable ftrace options and to get the name of
       an option.

       The tracefs_option_enable() function enables the option with id in the given instance. If
       instance is NULL, the option is enabled in the top trace instance.

       The tracefs_option_disable() function disables the option with id in the given instance.
       If instance is NULL, the option is disabled in the top trace instance.

       The tracefs_option_name() function returns a string, representing the option with id. The
       string must not be freed.

RETURN VALUE

       The tracefs_option_enable() and tracefs_option_disable() functions return 0 if the state
       of the option is set successfully, or -1 in case of an error.

       The tracefs_option_name() function returns string with option name, or "unknown" in case
       of an error. The returned string must not be freed.

EXAMPLE

           #include <tracefs.h>
           ...
           if (tracefs_option_enable(NULL, TRACEFS_OPTION_ANNOTATE)) {
                   /* Failed to enable annotate option in top trace instance */
           }
           ...
           if (tracefs_option_disable(NULL, TRACEFS_OPTION_CONTEXT_INFO)) {
                   /* Failed to disable context info option in top trace instance */
           }
           ...
           char *name = tracefs_option_name(TRACEFS_OPTION_FUNC_STACKTRACE);
           if (strcmp(name, "unknown")) {
                   /* Cannot get the name of the option */
           }

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