clarification on tap_timeout function

Hi Team,

I need a clarification the function "tap_timeout" which is being used in the runner.sh , the one will give the result format in the TAP 13 protocol. Below I am giving the function.

tap_timeout() { # Make sure tests will time out if utility is available. if [ -x /usr/bin/timeout ] ; then /usr/bin/timeout --foreground "$kselftest_timeout" "$1" else "$1" fi }

Need a clarification why we are using the function "tap_timout" and why the "kselftest_timeout" variable declared as 45 seconds by default. It will be very helpful if you are clarifying these things for me.

Regards Sarath PT