FAQs for Assignment 6

CSc 451, Spring 2003

Last Update: March 24, 2003, 6:20pm

Corrections

Problem 2, 3, 4:

Under "RESTRICTIONS", it should refer to problem 1 rather than problem 3.

Questions:

Q:      When I run expand it behaves like the cat command, simply echoing the input. Why?

A:      There's a utility named expand in /usr/local/bin and /usr/bin. If either directory appears in your path before ".", then running "expand" will run the utility. Use "./expand" to explicitly name the program in the current directory.

Q:      I'm having trouble matching the behavior of calc when a ^D is entered. Should I be worried about that?

A:      Don't worry about that.

Q:      What should calc do if the input is invalid, like a$b or x==1? Also, how about an empty line? (i.e., *read() = 0)

A:      Assume that the input is well-formed. No error cases will be tested. Use that assumption to simplify the code. Empty lines are considered to be not well-formed.

Q:      It looks like the reference version of xmlparse sorts the attributes by name, but the problem specification doesn't mention that. Does it matter?

A:      That's a bug in the specification—attributes should be sorted by name, just as the reference version does.