passfd on AIX 5.2

[Bruno Haible]

On AIX 5.1 and likely also 5.2, I get these warnings

passfd.c: In function 'sendfd':
passfd.c:60: warning: implicit declaration of function 'CMSG_SPACE'
passfd.c:67: warning: implicit declaration of function 'CMSG_LEN'

and later on link errors because CMSG_SPACE and CMSG_LEN are not functions.

The reason is that <sys/socket.h> defines these two macros only if
_LINUX_SOURCE_COMPAT is defined. This fixes it:


2011-03-13  Bruno Haible  <address@hidden>

        passfd: Fix link error on AIX 5.2.
        * m4/afunix.m4 (gl_SOCKET_AFUNIX): Define _LINUX_SOURCE_COMPAT.

--- m4/afunix.m4.orig   Sun Mar 13 23:59:07 2011
+++ m4/afunix.m4        Sun Mar 13 23:59:05 2011
@@ -1,4 +1,4 @@
-# afunix.m4 serial 4
+# afunix.m4 serial 5
 dnl Copyright (C) 2011 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -38,6 +38,10 @@
       [Define to 1 if <sys/socket.h> defines SCM_RIGHTS.])
   fi
 
+  dnl Persuade AIX 5.2 <sys/socket.h> to declare CMSG_SPACE, CMSG_LEN.
+  AC_DEFINE([_LINUX_SOURCE_COMPAT], [1],
+    [Define in order to get some macros on AIX systems.])
+
   AC_MSG_CHECKING([for UNIX domain sockets SCM_RIGHTS that behave in BSD4.4 
way])
   AC_CACHE_VAL([gl_cv_socket_unix_scm_rights_bsd44_way],
     [AC_COMPILE_IFELSE(
-- 
In memoriam Odette Sansom <http://en.wikipedia.org/wiki/Odette_Hallowes>