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An amazing directory: /proc (europe.pub)

submitted 1 day ago by cm0002@europe.pub to c/linux@programming.dev

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[-] trem 10 points 1 day ago

Just to kind of confirm this:

ls -l does not show them like hard links, but rather like soft/symbolic links.

But when I do tail -f /path/to/file.txt on a file (to keep it open in a process) and then delete the file, I get this output in ls -l:

3 -> '/path/to/file.txt (deleted)'

The 3 seems to just be an incrementing number for each file opened by the process. And then, well, obviously the file isn't now called "file.txt (deleted)". That is just a name the kernel makes up when ls -l asks it what's in that directory.

So, presumably the kernel keeps a separate copy of that file in memory until the process closes the file or is terminated. And then exposes it through this pseudo-softlink rather than making use of hardlinks.

[-] korthrun@piefed.social 6 points 1 day ago* (last edited 1 day ago)

The 3 seems to just be an incrementing number for each file opened by the process.

FWIW: https://en.wikipedia.org/wiki/File_descriptor#file_descriptor_table

If you throw an strace on a process that interacts with the filesystem you'll see that stuff like open() returns a file descriptor and stuff like read() takes a file descriptor as an argument.

These are also generally the numbers you're using when you do I/O redirection in your shell with stuff like 2>&1 or exec 5< ./some_file.txt

this post was submitted on 20 Aug 2026

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