Initial revision

m4/strerror_r.m4

@@ -0,0 +1,66 @@
+#serial 1002
+# Experimental replacement for the function in the latest CVS autoconf.
+# If the compile-test says strerror_r doesn't work, then resort to a
+# `run'-test that works on BeOS and segfaults on DEC Unix.
+# Use with the error.c file in ../lib.
+
+undefine([AC_FUNC_STRERROR_R])
+
+# AC_FUNC_STRERROR_R
+# ------------------
+AC_DEFUN([AC_FUNC_STRERROR_R],
+[AC_CHECK_DECLS([strerror_r])
+AC_CHECK_FUNCS([strerror_r])
+if test $ac_cv_func_strerror_r = yes; then
+  AC_CHECK_HEADERS(string.h)
+  AC_CACHE_CHECK([for working strerror_r],
+                 ac_cv_func_strerror_r_works,
+   [
+    AC_TRY_COMPILE(
+     [
+#       include <stdio.h>
+#       if HAVE_STRING_H
+#        include <string.h>
+#       endif
+     ],
+     [
+       char buf[100];
+       char x = *strerror_r (0, buf, sizeof buf);
+     ],
+     ac_cv_func_strerror_r_works=yes,
+     ac_cv_func_strerror_r_works=no
+    )
+    if test $ac_cv_func_strerror_r_works = no; then
+      # strerror_r seems not to work, but now we have to choose between
+      # systems that have relatively inaccessible declarations for the
+      # function.  BeOS and DEC UNIX 4.0 fall in this category, but the
+      # former has a strerror_r that returns char*, while the latter
+      # has a strerror_r that returns `int'.
+      # This test should segfault on the DEC system.
+      AC_TRY_RUN(
+       [
+#       include <stdio.h>
+#       include <string.h>
+#       include <ctype.h>
+
+	extern char *strerror_r ();
+
+	int
+	main ()
+	{
+	  char buf[100];
+	  char x = *strerror_r (0, buf, sizeof buf);
+	  exit (!isalpha (x));
+	}
+       ],
+       ac_cv_func_strerror_r_works=yes,
+       ac_cv_func_strerror_r_works=no,
+       ac_cv_func_strerror_r_works=no)
+    fi
+  ])
+  if test $ac_cv_func_strerror_r_works = yes; then
+    AC_DEFINE(HAVE_WORKING_STRERROR_R, 1,
+      [Define to 1 if `strerror_r' returns a string.])
+  fi
+fi
+])# AC_FUNC_STRERROR_R