Well ive also done this, checked filesize and compared it to a previous filesize to check for changes, but checking for filesize seems to "lock" it aswell.

The scripts needs to check the file every 3 seconds, because a certain trigger opens a popup after a certain action is made. So checking every 10 seconds would eliminate the problem but render the script useless.

If I open the log file in notepadd for editing, the program can still write to the file. Or am I right in thinking the file content will be loaded into mermory and the file is not in use until saving again.

Is it just PHP is locking it? Would a seperate windows app reading the file eliminate the problem?

Think im really stuck.
Thanks for your help so far though. Much appreciated!