gethostname() is more a BSD feature than an XOPEN one.

PR: 379

ssl/ssltest.c

@@ -114,7 +114,7 @@
  * SUN MICROSYSTEMS, INC., and contributed to the OpenSSL project.
  */
 
-#define _XOPEN_SOURCE 600	/* Or gethostname won't be declared properly
+#define _BSD_SOURCE 1		/* Or gethostname won't be declared properly
 				   on Linux and GNU platforms. */
 #define _XOPEN_SOURCE_EXTENDED	1 /* Or gethostname won't be declared properly
 				   on Compaq platforms (at least with DEC C).