8 ms·
Using extended attributes to tag files
- alance 10mo agoMy recent journey sorting through years of files and categorizing/tagging them with the built-in Extended File Attribute functionality.
- karmakaze 10mo agoI've lost extended attributes of files on a number of systems because they aren't always included by default in file operations. I don't trust everything that could possibly write/update a file to preserve them--common 'safe' pattern is to rename as .bak and write new file contents without EA to original name. Nor do I trust myself from archiving without using the right options in a hurry.
- alance 10mo agoYes concerning. The possibility of losing them between filesystems is worrying too. One rule of thumb is `mv` will keep the attributes by default (given similar filesystem) and everything else needs tweaking/extra args. There's a section on it over here: https://wiki.archlinux.org/title/Extended_attributes#Preserving_extended_attributes https://wiki.archlinux.org/title/Extended_attributes#Preserv...
- sureglymop 10mo agoSo you're telling me my size 0 file may unknowingly be a large key/value db? Neat. The system call to read these attributes is getxattr(), for anyone curious.
- alance 10mo agoHa, it suddenly sounds like trouble. Eg: one could piggy-back an entirely new file onto an existing file (it might have to be text encoded?). It looks like the kernel might impose a limit of 64KiB on a file's metadata, but that's still quite a lot of room for data smuggling...