Set time period for a statement to execute

[anand kumar]

Please guide me with some code or documentation for the following problem :-
   
  I need to set some specific time for a command to execute. For example, If I 
am opening a very large file and it takes me more than 3 to 4 seconds then my 
code should be able to quit the program or kill the process of opening the file 
and display an error message.
   
  Thanks in advance for the help
   
  -Anand

                        
---------------------------------
 Here’s a new way to find what you're looking for - Yahoo! Answers