sig sig

This event occurs when the signal is first delivered to the debugee. sig can either be a decimal number or the signal name in upper or lower case; the prefix is optional. This is completely independent of the catch/ignore commands, although the catch command can be implemented as follows:

function simple_catch {
	when sig $1 {
			stop;
			echo Stopped due to $sigstr $sig
			whereami
	}
}

When the sig event is received, the process has not seen it yet. Only if you cont the process with the given signal is the signal forwarded to it.