OpenCloudOS-Kernel/tools/lib/traceevent/Documentation/libtraceevent-handle.txt

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libtraceevent(3)
================
NAME
----
tep_alloc, tep_free,tep_ref, tep_unref,tep_get_ref - Create, destroy, manage
references of trace event parser context.
SYNOPSIS
--------
[verse]
--
*#include <event-parse.h>*
struct tep_handle pass:[*]*tep_alloc*(void);
void *tep_free*(struct tep_handle pass:[*]_tep_);
void *tep_ref*(struct tep_handle pass:[*]_tep_);
void *tep_unref*(struct tep_handle pass:[*]_tep_);
int *tep_get_ref*(struct tep_handle pass:[*]_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.
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.
EXAMPLE
-------
[source,c]
--
#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
-----
[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