Manual SIGWINCH handling.
Unix delivers notifications about tty size changes through the SIGWINCH signal. A handler for this signal is installed as soon as a new terminal is created. Replacing the global SIGWINCH handler using the Sys module will cause this module to malfunction, as the size change notifications will no longer be delivered.
You might still want to ignore resizes reported by event and directly listen to SIGWINCH. This module allows installing such listeners without conflicting with the rest of the machinery.
val add :
Unix.file_descr ->
((int * int) -> unit) ->
[ `Revert of unit -> unit ]add fd f registers a SIGWINCH handler. Every time the signal is delivered, f is called with the current size of the tty backing fd. If fd is not a tty, f is never called.
Return value is a function that removes the handler f.
Handlers are called in an unspecified order.