Updates the event mask to watch for the fd identified by
tag is the tag returned from g_source_add_unix_fd().
If you want to remove a fd, don’t set its event mask to zero. Instead, call g_source_remove_unix_fd().
This API is only intended to be used by implementations of
Do not call this API on a
GSource that you did not create.
As the name suggests, this function is not available on Windows.
Available since: 2.36
The tag from
The data is owned by the caller of the method.
The new event mask to watch.