+/*
+
+@deftypefn Supplemental char* index (char *@var{s}, int @var{c})
+
+Returns a pointer to the first occurrence of the character @var{c} in
+the string @var{s}, or @code{NULL} if not found. The use of @code{index} is
+deprecated in new programs in favor of @code{strchr}.
+
+@end deftypefn
+
+*/
+
+extern char * strchr(const char *, int);