Jul 132022

Not all shell aliases of course, but some. I’ve just seen a youtube video that suggested creating a shell alias to run rmtrash when rm is invoked :-

alias rm='rmtrash'

Seems sensible enough doesn’t it? This is in fact the classic example of how dangerous shell aliases can be, although the classic example was to turn on “-i” :-

alias rm='rm -i'

The problem is that you get used to “rm” being safe – either it asks before it removes files (“-i”) or it safely preserves what is deleted in the Trash folder. But what happens when the alias doesn’t get created? Perhaps you have a broken .zshrc and Zsh stops interpreting before the alias is declared. Or you’ve logged on to a remote server that doesn’t have your .zshrc installed as yet?

All of a sudden you are running the unadulterated rm command – deleting files without being asked, or preserving them in the Trash folder. See the danger now?

It is better not to replace standard commands but create a new ‘command’ :-

alias del="rmtrash"

Perhaps you regard this as being excessively risk averse – fair enough. But just don’t say you weren’t warned – and I’ve encountered missing aliases every year over the last 30-odd years I’ve been using Linux and Unix.

The Bare Family