Uses gettimeofday to retrieve the seconds and usec. It then uses these as part of the print rusage (prusage) routine, which displays the user CPU time used, system CPU time used, and the elapsed (wall-clock) time.
gettimeofday() is used here again to determine the amount of time it has taken to execute a command. The delta is then used in the builtin csh 'time' command.
gettimeofday(2) is used to get the time in seconds and usecs. These are used to timestamp the start of a i/o operation.
Gets the time in seconds and usec. gettimeofday(2) is used to timestamp the end of the i/o operation.