Provided by: libtracefs-doc_1.8.0-1ubuntu1_all
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