_single_threaded should have C linkage. Was for some reason only a

problem with gcc 4.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@24565 a95241bf-73f2-0310-859d-f6bbb57e9c96

headers/posix/stdio_post.h

@@ -14,11 +14,19 @@
 #	error "This file must be included from stdio.h!"
 #endif
 
+#ifdef __cplusplus
+extern "C" {
+#endif
+
 extern char _single_threaded;
 	// this boolean value is true (1) if there is only the main thread
 	// running - as soon as you spawn the first thread, it's set to
 	// false (0)
 
+#ifdef __cplusplus
+}
+#endif
+
 #define getc(stream) \
 	(_single_threaded ? getc_unlocked(stream) : getc(stream))
 #define putc(c, stream) \

headers/private/libroot/libroot_private.h

@@ -13,14 +13,14 @@
 struct user_space_program_args;
 struct real_time_data;
 
-extern char _single_threaded;
-	/* This determines if a process runs single threaded or not */
-
 
 #ifdef __cplusplus
 extern "C" {
 #endif
 
+extern char _single_threaded;
+	/* This determines if a process runs single threaded or not */
+
 status_t __parse_invoke_line(char *invoker, char ***_newArgs,
 			char * const **_oldArgs, int32 *_argCount, const char *arg0);
 status_t __get_next_image_dependency(image_id id, uint32 *cookie,