--- SIGCHLD {si_signo=SIGCHLD, si_code=CLD_EXITED, si_pid=15994, si_uid=0, si_status=0, si_utime=0, si_stime=0} ---
--- SIGCHLD {si_signo=SIGCHLD, si_code=CLD_EXITED, si_pid=15997, si_uid=0, si_status=0, si_utime=0, si_stime=2 /* 0.02 s */} ---
--- SIGCHLD {si_signo=SIGCHLD, si_code=CLD_EXITED, si_pid=15988, si_uid=0, si_status=0, si_utime=0, si_stime=0} ---
--- SIGCHLD {si_signo=SIGCHLD, si_code=CLD_EXITED, si_pid=15992, si_uid=0, si_status=0, si_utime=0, si_stime=0} ---
+++ exited with 0 +++