CS 3733 Operating Systems, Spring 2005 Assignment 4 Comments

General Comments:

• This assignment was graded on the basis of 30 points.
• Learn to use lint.
  From the comments on assignment 1:
  Each main program is linted with all of the pieces needed to run it.
  To run lint on the client program:
  lint FIFO_client.c utility.c restart.c I do not understand why people still cannot do this.
• A lint warning that sometimes return values are ignored is usually OK, but not in the case of strlen.
• You don't need to declare something as volatile just because it is used in a signal handler, only if it is changed in the handler.
• Do not use the signal system call.
• Save and restore errno in the signal handler if you are using print. This calls the lower level Unix functions (like write) which might change errno.
• If you are reading a variable in a signal handler, you should block the signals which changing the value of that variable unless it is of type sig_atomic_t. You cannot use this to safely store large values (like the size of a file).