Text File Manegement

Question

Dears i have a product that write the alerts on a text file i want to create an application to read these logs and i want to empty this file if it reach 2G in size the problem is that i am afraid that at the moment of deletion process the product write at the file and i loss this alert. Do you have any suggestions please ?

Vulpes · Answer

The same remarks which I've just made in your other thread about renaming files applies to deleting them: http://www.c-sharpcorner.com/Forums/Thread/186699/rename-text-file-used-by-two-applications.aspx However I am sympathetic to the point being made by theLizard. Are you sure that the application doesn't have its own mechanism for dealing with files which get too large?

theLizard · Answer

Using a filesystem watcher is ok for checking read / write operations but even if it is not writing at the time it is checked you cannot guarantee that it will not write to the file when in the process of deleting if this happens an access violation WILL ensue and destabilize the application that is attempting to write to the file. You should NOT be deleting files that you are not in control of because you have no idea what the application writing the file is doing.

Vulpes · Answer

I think you'll need to use a FileSystemWatcher to find out when the product is writing to the text file. Check out these links: http://msdn.microsoft.com/en-us/library/system.io.filesystemwatcher(VS.100).aspx http://www.blackwasp.co.uk/FileSystemWatcher.aspx

Areeb Asad · Answer

The problem is that i did not know when the product write to the log file whats i am afraid of the after checking the size and before deleting the product write to the file then the log is missed and i could not read it after that.

Vulpes · Answer

If you're writing to the log file before checking its size then clearly you need to check its size (and delete it if necessary) before writing to it. That of course means that you need to know the length in bytes of the next alert (say 'lenAlert') and then delete the file if it's already at least equal to (2 GB - lenAlert) bytes in size.