shell-portabilitylisted

# Shell Portability The standing trap list for script shell across distro families. Every entry came from a failure already observed on a real machine. Report each hit with its family and whether it fails loudly or silently. Where this list does not record loudness, verify on the machine before asserting it. Silent failures outrank loud ones. - Debian multiarch libdirs against `/usr/lib64` on RHEL-family layouts. A path built for one misses on the other. - `/usr/bin` against `/usr/sbin` for privileged binaries. Families merge or split them differently. - `/media/$USER` against `/run/media/$USER` for udisks mounts. - A read-only `/usr` under ostree systems (Silverblue and kin). - `case` statements with no default arm. The unmatched family falls through silently and the function returns success. - GNU-only flags on `find`, `sed`, `stat`, and `date`. - A `pkg_install` return value that kills the script under `set -e`, far from the cause. The adjacent trap is package naming, owned by the `parity` skill: read every distro package name off that distro's package database through `forge:web-browsing`, never from memory. The difference between `btrfs-progs` and `btrfsprogs` is one hyphen and a failed install on a machine nobody can test.