<signal.h> header file declares a type and
two functions and defines several macros for handling exception
conditions that might be reported during program execution.
signalfunction, and whose value compares unequal to the address of any declarable function.
void (*signal(int sig, void (*handler) (int))) (int);
SIG_ DFL, default handling of that signal occurs.
SIG_ IGN, the signal is ignored.
handleris called with the argument of the type of signal. Such a function is called a signal handler. Valid signals include:
Any other signals are operating-system dependent.
If the request can be honored, the
returns the value of
handler for the most
recent call to
signal for the specified signal
sig . Otherwise, a value of
returned and an implementation-defined positive value is stored
int raise(int sig);
sigto the executing program. The
raisefunction returns 0 if successful and nonzero if unsuccessful.