--- xscreensaver-4.18/driver/lock.c.check-for-null-passwd-entry 2007-04-18 16:25:33.000000000 -0400 +++ xscreensaver-4.18/driver/lock.c 2007-04-18 16:26:01.000000000 -0400 @@ -1289,7 +1289,7 @@ */ struct passwd *pw = getpwuid (getuid ()); char *d = DisplayString (si->dpy); - char *u = (pw->pw_name ? pw->pw_name : "???"); + char *u = (pw && pw->pw_name ? pw->pw_name : "???"); int opt = 0; int fac = 0;