zzuf tests: make compatible with *BSD by replacing obsoleted setpgrp() with setpgid().

ChangeLog

@@ -1,3 +1,6 @@
+Thu Apr 06 23:02:07 MSK 2017
+	Make zzuf tests compatible with *BSD platforms. -EG
+
 Thu Apr 06 22:14:22 MSK 2017
 	Added warning for hypothetical extra large timeout.
 	Fixed incorrect timeout calculation under extra rare conditions.

src/testzzuf/socat.c

@@ -88,7 +88,7 @@ zzuf_socat_start ()
         }
       return;
     }
-  setpgrp ();
+  setpgid (0, 0);
   execvp ("zzuf", args);
   fprintf (stderr, "execution of `zzuf' failed: %s\n", strerror (errno));
   zzuf_pid = 0;                 /* fork failed */