import exectime.d

example:

clu# dtrace -s exectime.d                                                                                                              ~
dtrace: script 'exectime.d' matched 6 probes
CPU     ID                    FUNCTION:NAME
  1   1074                      fork:create ksh pid 5112 ppid 4983
  2   1035        __mac_execve:exec-success ls pid 5123 ppid 5112 creation: 1208 us
  2   1119              exit1_internal:exit ls pid 5123 ppid 5112 lifetime: 4319 us
clarify the -xtemporal stuff