if (back->socket() != NULL) {
if (back != NULL && back->socket() != NULL) {
static void bump(char *fmt, ...){    char str[0x100]; /* Make the size big enough */    va_list ap;    va_start(ap, fmt);    strcpy(str, "Fatal:");    vsprintf(str+strlen(str), fmt, ap);    va_end(ap);    strcat(str, "\n");    tell_str(stderr, str);    if (back->socket() != NULL) {	char ch;	back->special(TS_EOF);	ssh_scp_recv(&ch, 1);    }    exit(1);}