+#if @GNULIB_GETLOGIN@
+/* Returns the user's login name, or NULL if it cannot be found. Upon error,
+ returns NULL with errno set.
+
+ See <http://www.opengroup.org/susv3xsh/getlogin.html>.
+
+ Most programs don't need to use this function, because the information is
+ available through environment variables:
+ ${LOGNAME-$USER} on Unix platforms,
+ $USERNAME on native Windows platforms.
+ */
+# if !@HAVE_GETLOGIN@
+extern char *getlogin (void);
+# endif
+#elif defined GNULIB_POSIXCHECK
+# undef getlogin
+# define getlogin() \
+ (GL_LINK_WARNING ("getlogin is unportable - " \
+ "use gnulib module getlogin for portability"), \
+ getlogin ())
+#endif
+
+