table of contents
| LIBTRACEEVENT(3) | libtraceevent Manual | LIBTRACEEVENT(3) |
NAME¶
tep_find_common_field, tep_find_field, tep_find_any_field - Search for a field in an event.
SYNOPSIS¶
#include <event-parse.h> struct tep_format_field *tep_find_common_field(struct tep_event *event, const char *name); struct tep_format_field *tep_find_field(struct tep_event_ormat *event, const char *name); struct tep_format_field *tep_find_any_field(struct tep_event *event, const char *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¶
#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¶
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¶
AUTHOR¶
Steven Rostedt <rostedt@goodmis.org[1]>, author of libtraceevent. Tzvetomir Stoyanov <tz.stoyanov@gmail.com[2]>, author of this man page.
REPORTING BUGS¶
Report bugs to <linux-trace-devel@vger.kernel.org[3]>
LICENSE¶
libtraceevent is Free Software licensed under the GNU LGPL 2.1
RESOURCES¶
https://git.kernel.org/pub/scm/libs/libtrace/libtraceevent.git/
NOTES¶
- 1.
- rostedt@goodmis.org
- 2.
- tz.stoyanov@gmail.com
- 3.
- linux-trace-devel@vger.kernel.org
| 04/04/2023 | libtraceevent 1.5.3 |