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#include <signal.h>int (*ssignal (sig, action))() int sig, (*action)();
int gsignal (sig) int sig;
The ssignal and gsignal functions implement a software facility similar to sigaction(S) and signal(S). This facility enables users to indicate the disposition of error conditions.
Software signals made available to users are associated with integers in the inclusive range 1 through 16. A call to ssignal associates a procedure, action, with the software signal sig; the software signal, sig, is raised by a call to gsignal. Raising a software signal causes the action established for that signal to be taken.
The first argument to ssignal is a number identifying the type of signal for which an action is to be established. The second argument defines the action; it is either the name of a (user-defined) action function or one of the manifest constants SIG_DFL (default) or SIG_IGN (ignore). The ssignal function returns the action previously established for that signal type; if no action has been established or the signal number is illegal, ssignal returns SIG_DFL.
The gsignal function raises the signal identified by its argument, sig:
If sig has an illegal value or no action was ever specified for sig, gsignal returns the value 0 and takes no other action.