[bug-diffutils] bug#24234: Recursive diff noise for broken symlinks, fifos and sockets

[Marcel Partap]

Dear diffutil devs,
when I copy large folder structures between harddisks, I like to check binary 
equality by running `diff -qr`. However, frequently the output is littered with 
powerful insights such as:
# File /mnt/source-xfs/repositories/kindlepdfviewer/emu_event is a fifo while 
file /usr/src/repositories/kindlepdfviewer/emu_event is a fifo
# File /mnt/source-xfs/repositories/android/i927-downloads/lost+found/#16412 is 
a socket while file 
/usr/src/repositories/android/i927-downloads/lost+found/#16412 is a socket
This does sound somewhat delusional.
Also, matching failures for broken symlinks:
# diff: /mnt/source-xfs/repositories/par2cmdline/test-driver: No such file or 
directory
# diff: /usr/src/repositories/par2cmdline/test-driver: No such file or directory
Additionally, recursive directory loops are being pointed out, but only on one 
side.

What I actually care for is missing and different files, not if there are 
broken symlinks, dir loops or fifos in the cloned directory hierarchy.
The documentation reads
>         -q, --brief
>                report only when files differ
so I think, it actually should do that. Is there any way at all fifos or 
sockets can actually differ?
I have no idea how to fix this, but hopefully someone else has : )

#Best Regards/Marcel Partap