@section @code{getprotobynumber}
@findex getprotobynumber
-POSIX specification: @url{http://www.opengroup.org/susv3xsh/getprotobynumber.html}
+POSIX specification: @url{http://www.opengroup.org/onlinepubs/9699919799/functions/getprotobynumber.html}
Gnulib module: ---