Faster DirectoryExists function?

Question

I use

DirectoryExists (const PathName : String);

to check if a directory is reachable from a computer or not. But if the directory does not exist and the path name is a network path, i.e.

\\computer1\Data

the method takes a very long time to return.

There must be a faster way to determine that a network folder is not reachable. Or can I configure some timeout parameter that DirectoryExists uses internally (I looked at the source code but it just delegates to GetFileAttributes which is defined in kernel32)?

Any ideas?

Answer 1

There is no faster way:

any function accessing anything on a remote share will timeout when that share is not available.

If the cause of your timeouts is automatic disconnecting of shares, then these link may help you:

• How Autodisconnect Works in Windows NT and Windows 2000
• Mapped Drive Connection to Network Share May Be Lost

If the application can continue without the completion of the check, then you can put the check in a separate thread, and upon completion of the check, you can update your status in the UI.

Be aware that when you try a multi-threading way, that you have to disprove your code is free of race-conditions and memory leaks. Time-outs in combination with exceptions usually make that a hard task.

Answer 2

There was the same question for C#: How to avoid network stalls in GetFileAttributes?

As codymanix said, use threads. The above link will show you how you can do it with delegates in C#. Don't know Delphi, but maybe you know how to convert the code?