tep_find_common_field, tep_find_field, tep_find_any_field - Search for a field in an event.

StevenRostedt <rostedt@goodmis.org[1]>, author of libtraceevent.
           TzvetomirStoyanov <tz.stoyanov@gmail.com[2]>, author of this man page.

       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.

           #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);
                   }
           }
           ...

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.

       libtraceevent is Free Software licensed under the GNU LGPL 2.1

       tep_find_common_field, tep_find_field, tep_find_any_field - Search for a field in an event.

        1. rostedt@goodmis.orgmailto:rostedt@goodmis.org

        2. tz.stoyanov@gmail.commailto:tz.stoyanov@gmail.com

        3. linux-trace-devel@vger.kernel.orgmailto:linux-trace-devel@vger.kernel.org

libtraceevent 1.8.4                                12/24/2024                                   LIBTRACEEVENT(3)

       Report bugs to <linux-trace-devel@vger.kernel.org[3]>

https://git.kernel.org/pub/scm/libs/libtrace/libtraceevent.git/

       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.

libtraceevent(3), trace-cmd(1)

#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);