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   poll.h.0p    ( 10 )

определения функции poll (definitions for the poll() function)

Пролог (Prolog)

This manual page is part of the POSIX Programmer's Manual. The Linux implementation of this interface may differ (consult the corresponding Linux manual page for details of Linux behavior), or the interface may not be implemented on Linux.


Имя (Name)

poll.h — definitions for the poll() function


Синопсис (Synopsis)

#include <poll.h>


Описание (Description)

The <poll.h> header shall define the pollfd structure, which shall include at least the following members:

int fd The following descriptor being polled. short events The input event flags (see below). short revents The output event flags (see below).

The <poll.h> header shall define the following type through typedef:

nfds_t An unsigned integer type used for the number of file descriptors.

The implementation shall support one or more programming environments in which the width of nfds_t is no greater than the width of type long. The names of these programming environments can be obtained using the confstr() function or the getconf utility.

The <poll.h> header shall define the following symbolic constants, zero or more of which may be OR'ed together to form the events or revents members in the pollfd structure:

POLLIN Data other than high-priority data may be read without blocking.

POLLRDNORM Normal data may be read without blocking.

POLLRDBAND Priority data may be read without blocking.

POLLPRI High priority data may be read without blocking.

POLLOUT Normal data may be written without blocking.

POLLWRNORM Equivalent to POLLOUT.

POLLWRBAND Priority data may be written.

POLLERR An error has occurred (revents only).

POLLHUP Device has been disconnected (revents only).

POLLNVAL Invalid fd member (revents only).

The significance and semantics of normal, priority, and high- priority data are file and device-specific.

The following shall be declared as a function and may also be defined as a macro. A function prototype shall be provided.

int poll(struct pollfd [], nfds_t, int);

The following sections are informative.


Использование в приложениях (Application usage)

None.


Обоснование (Rationale)

None.


Будущие направления (Future directions)

None.


Смотри также (See also)

The System Interfaces volume of POSIX.1‐2017, confstr(3p), poll(3p)

The Shell and Utilities volume of POSIX.1‐2017, getconf(1p)