Class 27: Files

Held: Wednesday, 5 March 2003

Summary: Today we consider C's key file input and output operations.

Related Pages:

• EBoard.
• Lab on files.

Assignments:

• Exam 1 (due Friday, 14 March 2003).

Notes:

• Lindsey's concert was cancelled. Sorry. No extra credit.
• I won't be in class on Friday. Daren and Mr. Gum will run a lab on curses or something else I/O related.
• Are there any final questions on homework 5?

Overview:

• The FILE type.
• Opening files.
• Reading from files.
• Writing to files.
• Lab.

Files

• You need to open them for reading or writing (or, sometimes, both).
• Normally treated as a stream of characters (similar to standard input and output).
• Open with fopen(path, mode).
• Returns a pointer to a FILE
• Read using fgetc or fscanf.
• Write using fputc or fprintf.
  • Confusing re-ordering of arguments.
• Make sure to close when you're done.

Lab

• We'll try a different kind of lab today. (One primarily written by Mr. Walker.)
• Do the lab.
• Be prepared to reflect.