'\" t .\" Title: libtraceevent .\" Author: [see the "AUTHOR" section] .\" Generator: DocBook XSL Stylesheets vsnapshot .\" Date: 01/14/2024 .\" Manual: libtraceevent Manual .\" Source: libtraceevent 1.8.2 .\" Language: English .\" .TH "LIBTRACEEVENT" "3" "01/14/2024" "libtraceevent 1\&.8\&.2" "libtraceevent Manual" .\" ----------------------------------------------------------------- .\" * Define some portability stuff .\" ----------------------------------------------------------------- .\" ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ .\" http://bugs.debian.org/507673 .\" http://lists.gnu.org/archive/html/groff/2009-02/msg00013.html .\" ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ .ie \n(.g .ds Aq \(aq .el .ds Aq ' .\" ----------------------------------------------------------------- .\" * set default formatting .\" ----------------------------------------------------------------- .\" disable hyphenation .nh .\" disable justification (adjust text to left margin only) .ad l .\" ----------------------------------------------------------------- .\" * MAIN CONTENT STARTS HERE * .\" ----------------------------------------------------------------- .SH "NAME" tep_parse_header_page \- Parses the data stored in the header page\&. .SH "SYNOPSIS" .sp .nf \fB#include \fR int \fBtep_parse_header_page\fR(struct tep_handle *\fItep\fR, char *\fIbuf\fR, unsigned long \fIsize\fR, int \fIlong_size\fR); .fi .SH "DESCRIPTION" .sp The \fBtep_parse_header_page()\fR function parses the header page data from \fIbuf\fR, and initializes the \fItep\fR, trace event parser context, with it\&. The buffer \fIbuf\fR is with \fIsize\fR, and is supposed to be copied from tracefs/events/header_page\&. .sp Some old kernels do not have header page info, in this case the \fBtep_parse_header_page()\fR function can be called with \fIsize\fR equal to 0\&. The \fItep\fR context is initialized with default values\&. The \fIlong_size\fR can be used in this use case, to set the size of a long integer to be used\&. .SH "RETURN VALUE" .sp The \fBtep_parse_header_page()\fR function returns 0 in case of success, or \-1 in case of an error\&. .SH "EXAMPLE" .sp .if n \{\ .RS 4 .\} .nf #include \&.\&.\&. struct tep_handle *tep = tep_alloc(); \&.\&.\&. char *buf; int size; buf = read_file("/sys/kernel/tracing/events/header_page", &size); if (tep_parse_header_page(tep, buf, size, sizeof(unsigned long)) != 0) { /* Failed to parse the header page */ } \&.\&.\&. .fi .if n \{\ .RE .\} .SH "FILES" .sp .if n \{\ .RS 4 .\} .nf \fBevent\-parse\&.h\fR Header file to include in order to have access to the library APIs\&. \fB\-ltraceevent\fR Linker switch to add when building a program that uses the library\&. .fi .if n \{\ .RE .\} .SH "SEE ALSO" .sp \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>, author of \fBlibtraceevent\fR\&. \fBTzvetomir Stoyanov\fR <\m[blue]\fBtz\&.stoyanov@gmail\&.com\fR\m[]\&\s-2\u[2]\d\s+2>, author of this man page\&. .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 libtraceevent is Free Software licensed under the GNU LGPL 2\&.1 .SH "RESOURCES" .sp \m[blue]\fBhttps://git\&.kernel\&.org/pub/scm/libs/libtrace/libtraceevent\&.git/\fR\m[] .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