+ with an error status.
+ - If termsigp is not NULL: *termsig will be set to the signal that
+ terminated the subprocess (if supported by the platform: not on native
+ Windows platforms), otherwise 0, and the error message about the signal
+ that terminated the subprocess will be omitted.
+ Prerequisites: The signal handler for SIGCHLD should not be set to SIG_IGN,
+ otherwise this function will not work. */