extern void xasprintf (char **ret, const char *format, ...) ATTR_FORMAT (printf, 2, 3);
extern void xvasprintf (char **ret, const char *format, va_list ap);
-/* Like asprintf, but return the string, throw an error if no memory. */
+/* Like asprintf and vasprintf, but return the string, throw an error
+ if no memory. */
extern char *xstrprintf (const char *format, ...) ATTR_FORMAT (printf, 1, 2);
+extern char *xstrvprintf (const char *format, va_list ap);
extern int parse_escape (char **);