libtraceevent(3)
|
================
|
|
NAME
|
----
|
tep_find_common_field, tep_find_field, tep_find_any_field -
|
Search for a field in an event.
|
|
SYNOPSIS
|
--------
|
[verse]
|
--
|
*#include <event-parse.h>*
|
|
struct tep_format_field pass:[*]*tep_find_common_field*(struct tep_event pass:[*]_event_, const char pass:[*]_name_);
|
struct tep_format_field pass:[*]*tep_find_field*(struct tep_event_ormat pass:[*]_event_, const char pass:[*]_name_);
|
struct tep_format_field pass:[*]*tep_find_any_field*(struct tep_event pass:[*]_event_, const char pass:[*]_name_);
|
--
|
|
DESCRIPTION
|
-----------
|
These functions search for a field with given name in an event. The field
|
returned can be used to find the field content from within a data record.
|
|
The _tep_find_common_field()_ function searches for a common field with _name_
|
in the _event_.
|
|
The _tep_find_field()_ function searches for an event specific field with
|
_name_ in the _event_.
|
|
The _tep_find_any_field()_ function searches for any field with _name_ in the
|
_event_.
|
|
RETURN VALUE
|
------------
|
The _tep_find_common_field(), _tep_find_field()_ and _tep_find_any_field()_
|
functions return a pointer to the found field, or NULL in case there is no field
|
with the requested name.
|
|
EXAMPLE
|
-------
|
[source,c]
|
--
|
#include <event-parse.h>
|
...
|
void get_htimer_info(struct tep_handle *tep, struct tep_record *record)
|
{
|
struct tep_format_field *field;
|
struct tep_event *event;
|
long long softexpires;
|
int mode;
|
int pid;
|
|
event = tep_find_event_by_name(tep, "timer", "hrtimer_start");
|
|
field = tep_find_common_field(event, "common_pid");
|
if (field == NULL) {
|
/* Cannot find "common_pid" field in the event */
|
} else {
|
/* Get pid from the data record */
|
pid = tep_read_number(tep, record->data + field->offset,
|
field->size);
|
}
|
|
field = tep_find_field(event, "softexpires");
|
if (field == NULL) {
|
/* Cannot find "softexpires" event specific field in the event */
|
} else {
|
/* Get softexpires parameter from the data record */
|
softexpires = tep_read_number(tep, record->data + field->offset,
|
field->size);
|
}
|
|
field = tep_find_any_field(event, "mode");
|
if (field == NULL) {
|
/* Cannot find "mode" field in the event */
|
} else
|
{
|
/* Get mode parameter from the data record */
|
mode = tep_read_number(tep, record->data + field->offset,
|
field->size);
|
}
|
}
|
...
|
--
|
|
FILES
|
-----
|
[verse]
|
--
|
*event-parse.h*
|
Header file to include in order to have access to the library APIs.
|
*-ltraceevent*
|
Linker switch to add when building a program that uses the library.
|
--
|
|
SEE ALSO
|
--------
|
_libtraceevent(3)_, _trace-cmd(1)_
|
|
AUTHOR
|
------
|
[verse]
|
--
|
*Steven Rostedt* <rostedt@goodmis.org>, author of *libtraceevent*.
|
*Tzvetomir Stoyanov* <tz.stoyanov@gmail.com>, author of this man page.
|
--
|
REPORTING BUGS
|
--------------
|
Report bugs to <linux-trace-devel@vger.kernel.org>
|
|
LICENSE
|
-------
|
libtraceevent is Free Software licensed under the GNU LGPL 2.1
|
|
RESOURCES
|
---------
|
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
|
