don't write to string constants

git-svn-id: svn://svn.h5l.se/heimdal/trunk/heimdal@9475 ec53bebd-3082-4978-b11e-865c3cabbd6b

appl/kx/common.c

@@ -601,6 +601,7 @@ find_auth_cookie (FILE *f)
     Xauth *ret = NULL;
     char local_hostname[MaxHostNameLen];
     char *display = getenv("DISPLAY");
+    char d[MaxHostNameLen + 4];
     char *colon;
     struct addrinfo *ai;
     struct addrinfo hints;
@@ -609,6 +610,8 @@ find_auth_cookie (FILE *f)
 
     if(display == NULL)
 	display = ":0";
+    strlcpy(d, display, sizeof(d));
+    display = d;
     colon = strchr (display, ':');
     if (colon == NULL)
 	disp = 0;