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[PATCH,HURD] hurdselect: remove dead code.
- From: Samuel Thibault <samuel dot thibault at gnu dot org>
- To: libc-alpha at sourceware dot org, roland at gnu dot org
- Cc: bug-hurd at gnu dot org
- Date: Sat, 5 Jan 2013 17:20:25 +0100
- Subject: [PATCH,HURD] hurdselect: remove dead code.
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.
hurdselect: remove dead code
* hurd/hurdselect.c (_hurd_select): Remove unreachable check for
diff --git a/hurd/hurdselect.c b/hurd/hurdselect.c
index 21ba5f4..fae21a2 100644
@@ -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;
/* At least one descriptor is known to be ready now, so we will
return success. */
err = 0;