PTHREAD_CLEANUP_PUSH(3C) Standard C Library Functions PTHREAD_CLEANUP_PUSH(3C)

NAME

pthread_cleanup_push - push a thread cancellation cleanup handler

SYNOPSIS

cc -mt [ flag... ] file... -lpthread [ library... ]
#include <pthread.h>

void pthread_cleanup_push(void (*handler) (void *), void *arg);

DESCRIPTION

The pthread_cleanup_push() function pushes the specified cancellation
cleanup handler routine, handler, onto the cancellation cleanup stack of
the calling thread.


When a thread exits or is canceled and its cancellation cleanup stack is
not empty, the cleanup handlers are invoked with the argument arg in
last in, first out (LIFO) order from the cancellation cleanup stack.


An exiting or cancelled thread runs with all signals blocked. All thread
termination functions, including cancellation cleanup handlers, are
called with all signals blocked.


The pthread_cleanup_push() and pthread_cleanup_pop(3C) functions can be
implemented as macros. The application must ensure that they appear as
statements, and in pairs within the same lexical scope (that is, the
pthread_cleanup_push() macro can be thought to expand to a token list
whose first token is '{' with pthread_cleanup_pop() expanding to a token
list whose last token is the corresponding '}').


The effect of the use of return, break, continue, and goto to prematurely
leave a code block described by a pair of pthread_cleanup_push() and
pthread_cleanup_pop() function calls is undefined.


Using longjmp() or siglongjmp() to jump into or out of a push/pop pair
can cause either the matching push or the matching pop statement not
getting executed.

RETURN VALUES

The pthread_cleanup_push() function returns no value.

ERRORS

No errors are defined.


The pthread_cleanup_push() function will not return an error code of
EINTR.

ATTRIBUTES

See attributes(7) for descriptions of the following attributes:


+--------------------+-------------------+
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+--------------------+-------------------+
|Interface Stability | Committed |
+--------------------+-------------------+
|MT-Level | MT-Safe |
+--------------------+-------------------+
|Standard | See standards(7). |
+--------------------+-------------------+

SEE ALSO

longjmp(3C), pthread_cancel(3C), pthread_cleanup_pop(3C),
pthread_exit(3C), pthread_join(3C), pthread_setcancelstate(3C),
pthread_setcanceltype(3C), pthread_testcancel(3C), attributes(7),
cancellation(7), condition(7), standards(7)

NOTES

See cancellation(7) for a discussion of cancellation concepts.

November 2, 2007 PTHREAD_CLEANUP_PUSH(3C)