ioCreateWatch
Creates a #GSource that's dispatched when @condition is met for the given @channel. For example, if condition is %G_IO_IN, the source will be dispatched when there's data available for reading.
The callback function invoked by the #GSource should be added with g_source_set_callback(), but it has type #GIOFunc (not #GSourceFunc).
g_io_add_watch() is a simpler interface to this same functionality, for the case where you want to add the source to the default main loop context at the default priority.
On Windows, polling a #GSource created to watch a channel for a socket puts the socket in non-blocking mode. This is a side-effect of the implementation and unavoidable.
Return
a new #GSource
Parameters
channel
a #GIOChannel to watch
condition
conditions to watch for