This is an internal utility module for use with the Alarm::*
alarm extensions, that handles tying of the Perl built-in
variable %SIG. This is deep magic and you use this module
at your own risk.
To use this class, simply use it and then call the
Alarm::_TieSIG::tiesig() function. This replaces %SIG with a dummy tied
Whenever the new %SIG is accessed, this class checks to see
if the requested key is ALRM. If so, it calls sethandler()
for STOREs, and gethandler() for FETCHes. You must provide
both of these methods in your package.
All other operations are passed on to the original, magic %SIG.
Note: Do not call tiesig() more than once. Doing so
produces a warning and no other effects.