Hello, This removes code which actually never happens, and is already taken care of in the function.
This is in the second part of select, when the __mach_msg() function over the portset has returned something else than MACH_MSG_SUCCESS. I guess in the past the value returned by __mach_msg() was stored in err, so this code was necessary to set back err to 0, but now it is stored in msgerr, so err is already still 0 by default. It can thus never contain MACH_RCV_TIMED_OUT, i.e. the code is dead. The first case mentioned in the comment is already handled: on time out with no message, err is already still the default 0. On time out due to poll, err would still be 0, unless some of the io_select RPCs has returned EINTR, in which case it contains EINTR. If any other io_select RPCs had returned a proper answer, got!=0, and thus err is set to 0 just below. The code is thus indeed not useful any more. Samuel hurdselect: remove dead code * hurd/hurdselect.c (_hurd_select): Remove unreachable check for MACH_RCV_TIMED_OUT. diff --git a/hurd/hurdselect.c b/hurd/hurdselect.c index 21ba5f4..fae21a2 100644 --- a/hurd/hurdselect.c +++ b/hurd/hurdselect.c @@ -407,14 +407,6 @@ _hurd_select (int nfds, } } - if (err == MACH_RCV_TIMED_OUT) - /* This is the normal value for ERR. We might have timed out and - read no messages. Otherwise, after receiving the first message, - we poll for more messages. We receive with a timeout of 0 to - effect a poll, so ERR is MACH_RCV_TIMED_OUT when the poll finds no - message waiting. */ - err = 0; - if (got) /* At least one descriptor is known to be ready now, so we will return success. */ err = 0;