-AC_CHECK_FUNCS(strerror)
-AC_CHECK_FUNCS(chmod close _close fork getpid _getpid lstat mkfifo mkstemp mktemp open _open pclose _pclose popen _popen readlink strerror)
-LYX_CHECK_DECL(istreambuf_iterator, iterator)
-LYX_CHECK_DECL(mkstemp,[unistd.h stdlib.h])
+LYX_CHECK_DEF(PATH_MAX, limits.h, [int n = PATH_MAX;])
+
+AC_CHECK_FUNCS(chmod close _close fork getpid _getpid lstat mkfifo open _open pclose _pclose popen _popen readlink strerror)