'\" t
.\"     Title: libtraceevent
.\"    Author: [see the "AUTHOR" section]
.\" Generator: DocBook XSL Stylesheets vsnapshot <http://docbook.sf.net/>
.\"      Date: 01/16/2026
.\"    Manual: libtraceevent Manual
.\"    Source: libtraceevent 1.8.4
.\"  Language: English
.\"
.TH "LIBTRACEEVENT" "3" "01/16/2026" "libtraceevent 1\&.8\&.4" "libtraceevent Manual"
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.nh
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.SH "NAME"
tep_parse_header_page \- Parses the data stored in the header page\&.
.SH "SYNOPSIS"
.sp
.nf
\fB#include <event\-parse\&.h>\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 <event\-parse\&.h>
\&.\&.\&.
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
