when the return value is null then you are at the end of the file. in a timer tick you can check at regularly intervals if someone has appended a line to the file. you also can do this with ReadLine, when it return null then nothing is appended, when it returns data then something is appended.

note that 'something' is not necessarily a complete line, it can be part of a line also, so you have to check for that also, and if the line is not complete then wait a moment and read again.

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rgds, Wilfried Mestdagh
www.mestdagh.biz
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