# libtraceevent(3) Manual Page

## NAME

tep_list_events, tep_list_events_copy - Get list of events, sorted by given criteria.

## SYNOPSIS

    #include <event-parse.h>

    enum tep_event_sort_type {
            TEP_EVENT_SORT_ID,
            TEP_EVENT_SORT_NAME,
            TEP_EVENT_SORT_SYSTEM,
    };

    struct tep_event **tep_list_events(struct tep_handle *tep, enum tep_event_sort_type sort_type);
    struct tep_event **tep_list_events_copy(struct tep_handle *tep, enum tep_event_sort_type sort_type);

## DESCRIPTION

The tep_list_events() function returns an array of pointers to the events, sorted by the sort_type criteria. The last element of the array is NULL. The returned memory must not be freed, it is managed by the library. The function is not thread safe. The tep argument is trace event parser context. The sort_type argument is the required sort criteria:

            TEP_EVENT_SORT_ID     - sort by the event ID.
            TEP_EVENT_SORT_NAME   - sort by the event (name, system, id) triplet.
            TEP_EVENT_SORT_SYSTEM - sort by the event (system, name, id) triplet.

The tep_list_events_copy() is a thread safe version of tep_list_events(). It has the same behavior, but the returned array is allocated internally and must be freed by the caller. Note that the content of the array must not be freed (see the EXAMPLE below).

## RETURN VALUE

The tep_list_events() function returns an array of pointers to events. In case of an error, NULL is returned. The returned array must not be freed, it is managed by the library.

The tep_list_events_copy() function returns an array of pointers to events. In case of an error, NULL is returned. The returned array must be freed by the caller.

## EXAMPLE

    #include <event-parse.h>
    ...
    struct tep_handle *tep = tep_alloc();
    ...
    int i;
    struct tep_event_format **events;

    i=0;
    events = tep_list_events(tep, TEP_EVENT_SORT_ID);
    if (events == NULL) {
            /* Failed to get the events, sorted by ID */
    } else {
            while(events[i]) {
                    /* walk through the list of the events, sorted by ID */
                    i++;
            }
    }

    i=0;
    events = tep_list_events_copy(tep, TEP_EVENT_SORT_NAME);
    if (events == NULL) {
            /* Failed to get the events, sorted by name */
    } else {
            while(events[i]) {
                    /* walk through the list of the events, sorted by name */
                    i++;
            }
            free(events);
    }

    ...

## 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

libtraceevent(3), trace-cmd(1)

## AUTHOR

    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/libs/libtrace/libtraceevent.git/