"""This module provides mechanisms to use signal handlers in Python.

Functions:

alarm() -- cause SIGALRM after a specified time [Unix only]
setitimer() -- cause a signal (described below) after a specified
               float time and the timer may restart then [Unix only]
getitimer() -- get current value of timer [Unix only]
signal() -- set the action for a given signal
getsignal() -- get the signal action for a given signal
pause() -- wait until a signal arrives [Unix only]
default_int_handler() -- default SIGINT handler

signal constants:
SIG_DFL -- used to refer to the system default handler
SIG_IGN -- used to ignore the signal
NSIG -- number of defined signals
SIGINT, SIGTERM, etc. -- signal numbers

itimer constants:
ITIMER_REAL -- decrements in real time, and delivers SIGALRM upon
               expiration
ITIMER_VIRTUAL -- decrements only when the process is executing,
               and delivers SIGVTALRM upon expiration
ITIMER_PROF -- decrements both when the process is executing and
               when the system is executing on behalf of the process.
               Coupled with ITIMER_VIRTUAL, this timer is usually
               used to profile the time spent by the application
               in user and kernel space. SIGPROF is delivered upon
               expiration.


*** IMPORTANT NOTICE ***
A signal handler function is called with two arguments:
the first is the signal number, the second is the interrupted stack frame."""

CTRL_BREAK_EVENT=1
CTRL_C_EVENT=0
NSIG=23
SIGABRT=22
SIGBREAK=21
SIGFPE=8
SIGILL=4
SIGINT=2
SIGSEGV=11
SIGTERM=15
SIG_DFL=0
SIG_IGN=1

def signal(signalnum, handler) :
    pass