CIS 432/532 Introduction to Computer Networks
Winter 2001

Program #2 FAQ

1. Q: Are the Qt libraries installed on the department's Solaris systems?
   A: Yes. We have version 2.1.1 installed in /local/apps/Libraries/qt-2.1.1/ (the latest version appears to be 2.2.4). There is also a link in /local/lib so you should use that path for compiling. Before you try using Qt, be sure to make a version with that uses standard input and output first.
   
   
2. Q: How do I handle a user's message with just a "." (period) on a line? If I write this to the mail server, it will think the message has ended.
   A: You should check the first character of every line in the message. If the first character is a period, then add an additional period in front of it. See this excerpt from RFC 821:
   
   "1. Before sending a line of mail text the sender-SMTP checks
   the first character of the line. If it is a period, one
   additional period is inserted at the beginning of the line.
   2. When a line of mail text is received by the receiver-SMTP
   it checks the line. If the line is composed of a single
   period it is the end of mail. If the first character is a
   period and there are other characters on the line, the first
   character is deleted."
   
   There's lots of other useful things in this RFC -- be sure to read it.
   
   
3. Q: Why is the mail server giving me reply codes that look like: 250 2.1.0?
   A: These are enhanced status codes -- see RFC 1893.
   
   
4. Q: How should I handle a bad address? Do I need to use the GUI to display a new window, or can I just notify the user on standard output?
   A: I would prefer that you handle it through the GUI, but if you don't know how to do this then it is OK to use standard output. Whatever method you use, the user should be able to re-enter a good address. The application should not quit after the error is detected.