This patch fixes a segmentation violation in mod_proxy when a
response is non-cachable.  Problem reported by Doug Bloebaum.

Index: modules/proxy/proxy_util.c
===================================================================
RCS file: /home/cvs/apache-1.3/src/modules/proxy/proxy_util.c,v
retrieving revision 1.70
diff -u -r1.70 proxy_util.c
--- proxy_util.c	1998/08/31 19:51:59	1.70
+++ proxy_util.c	1998/10/09 16:21:14
@@ -581,7 +581,7 @@
                 ap_reset_timeout(r);
 
             if (w <= 0) {
-                if (c != NULL) {
+                if (c != NULL && c->fp != NULL) {
                     /* when a send failure occurs, we need to decide
                      * whether to continue loading and caching the
                      * document, or to abort the whole thing