this post was submitted on 12 Dec 2023
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  • ISO 8601 is paywalled
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[–] meekah 4 points 1 year ago* (last edited 1 year ago) (1 children)

but what does the command line matter for dates? sure every once in a while you'll have to pass a date as an argument on the command line but I think usually that kind of data is handled by APIs without human intervention, so once these are set up properly, I don't see the problem

[–] rtxn 22 points 1 year ago (3 children)
rsync -a "somedir" "somedir_backup_$(date)"

If the date command returns an RFC-3339-formatted string, the filename will contain a space. If, for example, you want to iterate over the files using for d in $(find...) and forget to set $IFS properly, it can cause issues.

[–] [email protected] 2 points 1 year ago (1 children)

But $(date) does return a string with spaces, at least on every system I've ever used. And what's so bad about the possibility of spaces in filenames? They're slightly inconvenient in a command line, but I haven't used a commuter this century that didn't support spaces in filenames.

[–] rtxn 4 points 1 year ago (1 children)

Bro, literally re-read the comment you replied to. It has an example of what might happen.

[–] [email protected] 1 points 1 year ago* (last edited 1 year ago) (1 children)

Ok, I just reread it. I don't see what you think I'm missing. You mean an improperly written find command misbehaving? The fact that a different date format could prevent a bug from manifesting doesn't seem like much of an argument.

[–] [email protected] 2 points 1 year ago (1 children)

Spaces can exist in filenames. The only problem is that they have to be escaped. As the comment that you reread explained, cat hello world.txt would print the files hello and world.txt. If you wanted to print the file "hello world.txt" you'd either need to quote it (cat "hello world.txt") or escape the space (cat hello\ world.txt)

[–] [email protected] 2 points 1 year ago

Oh, the horror!

[–] calcopiritus 1 points 1 year ago (1 children)

Both arguments are surrounded by ", which should be space-safe.

At least in the shells I use, putting " makes spaces inside paths a non-issue.

[–] rtxn 1 points 1 year ago

For the rsync command, yes. But this:

for d in $(find . -type d); do
    echo "$d"
done

will process the space-separated parts of each path as separate items. I had to work around this issue just two days ago, it's an obscure thing that not everyone will keep in mind.