int __raise(int signal, int type);

where:

This function calls the normal C signal mechanism or the default signal handler.

You can replace the __raise() function by defining:

int __raise(int signal, int type);

This enables you to bypass the C signal mechanism and its data-consuming signal handler vector, but otherwise gives essentially the same interface as:

void __default_signal_handler(int signal, int type);

The default signal handler of the library uses the type parameter of __raise() to vary the messages it outputs.

There are three possibilities for a __raise() return condition: