tep_alloc - Man Page

Create, destroy, manage references of trace event parser context.

Synopsis

#include <event-parse.h>

struct tep_handle *tep_alloc(void);
void tep_free(struct tep_handle *tep);
void tep_ref(struct tep_handle *tep);
void tep_unref(struct tep_handle *tep);
int tep_get_ref(struct tep_handle *tep);
struct kbuffer *tep_kbuffer(struct tep_handle *tep);

Description

These are the main functions to create and destroy tep_handle - the main structure, representing the trace event parser context. This context is used as the input parameter of most library APIs.

The tep_alloc() function allocates and initializes the tep context.

The tep_free() function will decrement the reference of the tep handler. When there is no more references, then it will free the handler, as well as clean up all its resources that it had used. The argument tep is the pointer to the trace event parser context.

The tep_ref() function adds a reference to the tep handler.

The tep_unref() function removes a reference from the tep handler. When the last reference is removed, the tep is destroyed, and all resources that it had used are cleaned up.

The tep_ref_get() functions gets the current references of the tep handler.

The tep_kbuffer() function allocates a kbuffer descriptor that can be used to parse raw data that is represented by the tep handle descriptor. It must be freed with kbuf_free(3).

Return Value

tep_alloc() returns a pointer to a newly created tep_handle structure. NULL is returned in case there is not enough free memory to allocate it.

tep_ref_get() returns the current references of tep. If tep is NULL, 0 is returned.

tep_kbuffer() returns a kbuffer descriptor that can parse the raw data that represents the tep handle. Must be freed with kbuf_free(3).

Example

#include <event-parse.h>

...
struct tep_handle *tep = tep_alloc();
...
int ref = tep_get_ref(tep);
tep_ref(tep);
if ( (ref+1) != tep_get_ref(tep)) {
        /* Something wrong happened, the counter is not incremented by 1 */
}
tep_unref(tep);
...
tep_free(tep);
...

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[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
    mailto:rostedt@goodmis.org
  2. tz.stoyanov@gmail.com
    mailto:tz.stoyanov@gmail.com
  3. linux-trace-devel@vger.kernel.org
    mailto:linux-trace-devel@vger.kernel.org

Referenced By

tracefs_local_events(3).

The man pages tep_free(3), tep_get_ref(3), tep_kbuffer(3), tep_ref(3) and tep_unref(3) are aliases of tep_alloc(3).

10/17/2024 libtraceevent 1.8.4 libtraceevent Manual