Re: [Solved] Difficulty with a shell function.

[peter@easthope.ca]

From: Greg Wooledge <greg@wooledge.org>
Date: Sun, 25 Jan 2026 15:26:19 -0500
> What?

My knowledge of ISO 9660 is cursory but note the first sentence 
in https://en.wikipedia.org/wiki/Optical_disk_image ,
"... disk image ... written to an optical disk, disk sector by disc sector ...".
Not directly comparable to ext4.

> > 2026-01-19-03-28-45-00. Shorter than a UUID for a file system.
> 
> This looks like a timestamp.

Explained by Thomas Schmitt in <[🔎] 16912500410373272277@scdbackup.webframe.org>

>> lsblk --nodeps -o name,serial | grep -F -- "$destination" | cut -d ' ' -f1 

> So... you *have* the serial number (somehow) ...

As you did.
# lsblk --nodeps -o name,serial

> The obvious way would be to use awk: ...

OK, thanks.  cut, awk and others.  cut seemed straightforward.

> awk -v isn't 100% safe with all inputs, but if your serial number is
> reasonable (alphanumeric, maybe with some basic punctuation, but no
> backslashes or control characters) it should be OK.

The cut I used relied only on blank separation.

Thanks,                          ... P.

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