Calling the gsignal function has one of the following results: o If gsignal specifies a sig argument that is outside the range defined in the <signal.h> header file, then gsignal returns 0 and sets errno to EINVAL. o If signal, ssignal, or sigvec establishes SIG_DFL (default action) for the signal, then gsignal does not return. The image is exited with the OpenVMS error code corresponding to the signal. o If signal, ssignal, or sigvec establishes SIG_IGN (ignore signal) as the action for the signal, then gsignal returns its argument, sig. o signal, ssignal, or sigvec must be used to establish an action routine for the signal. That function is called and its return value is returned by gsignal. See the Error and Signal Handling chapter of the C RTL Reference Manual for more information. See also raise, signal, ssignal, and sigvec.