How does \cp work?

Question

I know that if you have some alias with the name cp, you can bypass it using \cp.

Is this unix syntax? Are there any other uses of this syntax?

Answer 1

It's a feature of the shell and seems to be common to both the Bourne shell family (sh, ksh, bash, zsh) and the C shell family (csh, tcsh). It's based on character escaping. By escaping the first character (actually you can escape any character) it prevents alias expansion from being performed.

$ alias cp='echo hello'
$ cp -v from to
hello -v from to
$ c\p from to
`from' -> `to'

Escaping is used a lot. For just a very brief introduction to a small part of the usefulness of escaping, see the Quoting section in man bash.