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Signal handling may not behave as on Unix platforms (where
it doesn't exactly "behave", either). For instance,
calling "die()" or "exit()" from signal handlers will
cause an exception, since most implementations of "sig-
nal()" on Win32 are severely crippled. Thus, signals may
work only for simple things like setting a flag variable
in the handler. Using signals under this port should cur-
rently be considered unsupported.