time

time command
time [command]

Korn shell only. Execute command and print the total elapsed time, user time, and system time (in seconds). Same as the Unix command time (see Chapter 2), except that the built-in version can also time other built-in commands as well as all commands in a pipeline.

The second form applies to ksh93; with no command, the total user and system times for the shell, and all children are printed.