I need to try it out, but it does look like it could work. Only I would need to create two new files using more disk space, and I was hoping to use pure perl. I also need to see how to work the output of comm.

My data looks as follows. The keys I was referring to is the path of a file or directory, where file/directory sizes can change and files/directories may/may not exist in file1 compared file2

File1:
/home/users/ DIR 5555
/home/users/file FILE 324
/home/users/file2 FILE 435
....
....

File2:
/home/users/file FILE 555
/home/users/ DIR 5888
/home/users/file2 FILE 435
....
....
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