Optionally registers this extension with the signal extension and
activates the handling of the specified signal, which will cause the
registered files to be reopened. For this to happen, a non-null
signal_ext and a non-zero reopen_signal must be supplied.
Constructor.
Optionally registers this extension with the signal extension and activates the handling of the specified signal, which will cause the registered files to be reopened. For this to happen, a non-null signal_ext and a non-zero reopen_signal must be supplied.