add_poll

Adds a file descriptor to the set of file descriptors polled for this source.

This is usually combined with [ctor@GLib.Source.new] to add an event source. The event source’s check function will typically test the revents field in the [struct@GLib.PollFD] struct and return true if events need to be processed.

This API is only intended to be used by implementations of [struct@GLib.Source]. Do not call this API on a [struct@GLib.Source] that you did not create.

Using this API forces the linear scanning of event sources on each main loop iteration. Newly-written event sources should try to use `g_source_add_unix_fd()` instead of this API.

Parameters:

this	a source
fd	a [struct@GLib.PollFD] structure holding information about a file descriptor to watch