See Section A.11 for answers to the following exercises.
1. [12] Write a program to ask the user for a directory name, then change to that directory. If the user enters a line with nothing but whitespace, change to his or her home directory as a default. After changing, list the ordinary directory contents (not the items whose names begin with a dot) in alphabetical order. (Hint: Will that be easier to do with a directory handle or with a glob?) If the directory change doesn't succeed, just alert the user but don't try show the contents.
2. [4] Modify the program to include all files, not just the ones that don't begin with a dot.
3. [5] If you used a directory handle for the previous exercise, rewrite it to use a glob. Or if you used a glob, try it now with a directory handle.