select_query()

Декодировать последнее событие выбора

Прототип:

#include <sys/iofunc.h>
#include <sys/dispatch.h>
int select_query( select_context_t *ctp,
int *fd,
unsigned *flags,
int (**func)( select_context_t *ctp,
int fd,
unsigned flags,
void *handle ),
void **handle );

Аргументы:

ctp
A pointer to a select_context_t structure that defines the context of the event that you want to get information about.
fd
A pointer to a location where the function can store the file descriptor that's associated with the event.
flags
A pointer to a location where the function can store the flags associated with the event; see Флаги in the documentation for select_attach().
func
A pointer to a location where the function can store the function associated with the event; see Function in the documentation for select_attach().
handle
A pointer to a location where the function can store the address of any data that you arranged to pass to func.

Библиотека:

libc

Описание:

The function select_query() stores the values of the last select event, for context ctp, in fd, flags, func, and handle.

Возвращаемое значение:

If an error occurs, the function returns -1. An error occurs if the received event doesn't belong to one of the file descriptors attached with select_attach().

Примеры:

#include <sys/dispatch.h>
#include <stdio.h>
#include <stdlib.h>
#include <fcntl.h>
int my_func( select_context_t *ctp, int fd, unsigned flags, void *handle )
{
...
}
int main( int argc, char **argv )
{
dispatch_t *dpp;
dispatch_context_t *ctp;
int fd;
unsigned flag;
void *handle;
select_attr_t *attr;
int (*func)( select_context_t *, int, unsigned, void * );
if ( ( dpp = dispatch_create() ) == NULL )
{
fprintf( stderr, "%s: Unable to allocate dispatch handle.\n", argv[0] );
return (EXIT_FAILURE);
}
if ( argc ≤ 2 || (fd = open( argv[1], O_RDWR | O_NONBLOCK )) == -1 )
{
exit( 0 );
}
select_attach( dpp, attr, fd, SELECT_FLAG_READ | SELECT_FLAG_REARM,
&my_func, NULL );
ctp = dispatch_context_alloc( dpp );
...
if ( select_query( (select_context_t *)ctp, &fd, &flag,
&func, &handle ) == -1 )
{
fprintf( stderr, "Failed to decode last select event.\n" );
return (1);
}
}

For more examples using the dispatch interface, see dispatch_create(), message_attach(), resmgr_attach(), and thread_pool_create().

Классификация:

ЗОСРВ «Нейтрино»

Точка остановки потока
Нет
Обработчик прерываний
Нет
Обработчик сигналов
Нет
В потоке
Да

Тематические ссылки:

select_attach(), select_detach()




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