Another stupid MSVC ctype macro assertion avoidance typecast.

src/sbbs3/main.cpp

@@ -252,7 +252,7 @@ u_long resolve_ip(char *addr)
 		return((u_long)INADDR_NONE);
 
 	for(p=addr;*p;p++)
-		if(*p!='.' && !isdigit(*p))
+		if(*p!='.' && !isdigit((uchar)*p))
 			break;
 	if(!(*p))
 		return(inet_addr(addr));