Add skalibs/posixishard.h

 This will break things. It's a known issue. Patches to other
packages will come later, to adapt them to the new API.

 To work around brokenness, there needs to be *two* different
headers:
 1. one to be used before including system headers, that maximizes
visibility by enabling system-dependent feature test macros
(that will be tested by system headers)
 2. one to be used after including system headers, that performs
preprocessor tests and defines.

 skalibs/nonposix.h is the first one.
 Previously, there was no second one, and the tests were scattered
all over. There was a strnlen declaration in skalibs/posixplz.h
(which serves a totally different function: declaring things that
should be in POSIX, but *are not*, i.e. working around problems in
the standard, instead of problems in systems failing to respect
the standard), a build-time sysdep for error.h, #defines for
MSG_NOSIGNAL, etc. etc.
 skalibs/posixishard.h now is the second one, and centralizes
all the tests.

 As a result, the eproto sysdep is unnecessary and has been removed.
skalibs/error.h is now a static header, it is not built anymore.

1 files changed, 3 insertions, 5 deletions

diff --git a/src/libunixonacid/unixmessage_sender_flush.c b/src/libunixonacid/unixmessage_sender_flush.c
index fa1438f..3f096f0 100644
--- a/src/libunixonacid/unixmessage_sender_flush.c
+++ b/src/libunixonacid/unixmessage_sender_flush.c
@@ -1,12 +1,15 @@
 /* ISC license. */
 
 #include <skalibs/nonposix.h>
+
 #include <sys/socket.h>
 #include <sys/uio.h>
 #include <string.h>
 #include <stdint.h>
 #include <unistd.h>
 #include <errno.h>
+
+#include <skalibs/posixishard.h>
 #include <skalibs/uint16.h>
 #include <skalibs/uint32.h>
 #include <skalibs/disize.h>
@@ -15,11 +18,6 @@
 #include <skalibs/djbunix.h>
 #include <skalibs/unixmessage.h>
 
- /* MacOS X tries hard to be POSIX-compliant... and fails. */
-#ifndef MSG_NOSIGNAL
-#define MSG_NOSIGNAL 0
-#endif
-
 union aligner_u
 {
   struct cmsghdr cmsghdr ;