'\" t
.\"     Title: libtracefs
.\"    Author: [see the "AUTHOR" section]
.\" Generator: DocBook XSL Stylesheets vsnapshot <http://docbook.sf.net/>
.\"      Date: 10/08/2022
.\"    Manual: libtracefs Manual
.\"    Source: libtracefs 1.5.0
.\"  Language: English
.\"
.TH "LIBTRACEFS" "3" "10/08/2022" "libtracefs 1\&.5\&.0" "libtracefs Manual"
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.SH "NAME"
tracefs_option_enable, tracefs_option_disable, tracefs_option_name \- Various trace option functions\&.
.SH "SYNOPSIS"
.sp
.nf
\fB#include <tracefs\&.h>\fR

int \fBtracefs_option_enable\fR(struct tracefs_instance *\fIinstance\fR, enum tracefs_option_id \fIid\fR);
int \fBtracefs_option_disable\fR(struct tracefs_instance *\fIinstance\fR, enum tracefs_option_id \fIid\fR);
const char *\fBtracefs_option_name\fR(enum tracefs_option_id \fIid\fR);
.fi
.SH "DESCRIPTION"
.sp
This set of APIs can be used to enable and disable ftrace options and to get the name of an option\&.
.sp
The \fBtracefs_option_enable()\fR function enables the option with \fIid\fR in the given \fIinstance\fR\&. If \fIinstance\fR is NULL, the option is enabled in the top trace instance\&.
.sp
The \fBtracefs_option_disable()\fR function disables the option with \fIid\fR in the given \fIinstance\fR\&. If \fIinstance\fR is NULL, the option is disabled in the top trace instance\&.
.sp
The \fBtracefs_option_name()\fR function returns a string, representing the option with \fIid\fR\&. The string must \fBnot\fR be freed\&.
.SH "RETURN VALUE"
.sp
The \fBtracefs_option_enable()\fR and \fBtracefs_option_disable()\fR functions return 0 if the state of the option is set successfully, or \-1 in case of an error\&.
.sp
The \fBtracefs_option_name()\fR function returns string with option name, or "unknown" in case of an error\&. The returned string must \fBnot\fR be freed\&.
.SH "EXAMPLE"
.sp
.if n \{\
.RS 4
.\}
.nf
#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 */
}
.fi
.if n \{\
.RE
.\}
.SH "FILES"
.sp
.if n \{\
.RS 4
.\}
.nf
\fBtracefs\&.h\fR
        Header file to include in order to have access to the library APIs\&.
\fB\-ltracefs\fR
        Linker switch to add when building a program that uses the library\&.
.fi
.if n \{\
.RE
.\}
.SH "SEE ALSO"
.sp
\fBlibtracefs\fR(3), \fBlibtraceevent\fR(3), \fBtrace\-cmd\fR(1)
.SH "AUTHOR"
.sp
.if n \{\
.RS 4
.\}
.nf
\fBSteven Rostedt\fR <\m[blue]\fBrostedt@goodmis\&.org\fR\m[]\&\s-2\u[1]\d\s+2>
\fBTzvetomir Stoyanov\fR <\m[blue]\fBtz\&.stoyanov@gmail\&.com\fR\m[]\&\s-2\u[2]\d\s+2>
.fi
.if n \{\
.RE
.\}
.SH "REPORTING BUGS"
.sp
Report bugs to <\m[blue]\fBlinux\-trace\-devel@vger\&.kernel\&.org\fR\m[]\&\s-2\u[3]\d\s+2>
.SH "LICENSE"
.sp
libtracefs is Free Software licensed under the GNU LGPL 2\&.1
.SH "RESOURCES"
.sp
\m[blue]\fBhttps://git\&.kernel\&.org/pub/scm/libs/libtrace/libtracefs\&.git/\fR\m[]
.SH "COPYING"
.sp
Copyright (C) 2020 VMware, Inc\&. Free use of this software is granted under the terms of the GNU Public License (GPL)\&.
.SH "NOTES"
.IP " 1." 4
rostedt@goodmis.org
.RS 4
\%mailto:rostedt@goodmis.org
.RE
.IP " 2." 4
tz.stoyanov@gmail.com
.RS 4
\%mailto:tz.stoyanov@gmail.com
.RE
.IP " 3." 4
linux-trace-devel@vger.kernel.org
.RS 4
\%mailto:linux-trace-devel@vger.kernel.org
.RE