Evtek				Real-time programming
HL				CP00S Spring 2004


Exercise 2. (Using system calls)


      Write a program that has the following features:

      First the program displays the POSIX-version that the 
      system supports.

      Sedondly the program displays the date and time in the
      format usually used in Finland, that is in the format 

      	dd.mm.yyyy hh:mm:ss

      
      Thirdly the program displays the contents of a text
      file containg some (for example 5) integers, one integer
      at a line. First the program prompts user to enter the
      name of the file. If user enters a file name that does
      not exists, the program displays an error message. In
      similkar way, if the user has not right to access the file 
      the error message is displayed. In each of these error 
      situation, the program also displays the reason of error
      according the error code,

      It is required, that system calls (not library function
      calls) are used to handle files (this means that you 
      have to use fuctions open, write and close).

                 
      Remark 1. The end of file must be handled correctly
      without the knowledle of how many lines the file contains. 
 
      Remark 2. Use for example Emacs to edit a small test file
      containing five or so integer number lines that you can
      use to test the program.