I am opening a file in read mode and reading continuosly after a time interval from 9AM to 4PM. Two problems exist: (1) Few lines from the file have been missed for certain time interval alone, able to read the contents after the missed lines. (2) Continuously checking the file and coming out as no new lines have been added to the file after certain time till I restart my application.

My application is only opening the file in read mode and reading data once in 30 secs or so. Another application is writing data to the file from 9AM to 4 PM. What might be the problem?