pattern for matching a filepath

Question

Can you please tell me the grep pattern for matching the following filepath:

../any_directoryname/filename.txt

I only know the filename. The any_directoryname keeps on changing.

Thanks in advance,

Regards

John

Answer 1

Try this:

\.\./[^/]+/filename.txt

This assumes only one directory. If it can be more than that, try

\.\./[^\r\n]+/filename.txt