Using parentheses in bash commands, git mv

Question

Trying to rename a file using parentheses but I keep hitting this error and can't find any docs around it:

-bash: syntax error near unexpected token `('

I'm doing something like:

git mv title_1.1 title_(1.1)

Answer 1

Parentheses are special to shells -- they're used when defining function, declaring arrays, using command substitution and for subshells.

To use them literally, as in filenames, just add appropriate quoting:

git mv title_1.1 "title_(1.1)"

Note Mat's warning though. This is a medium risk filename that may cause certain poorly written tools and scripts to choke. It's better than having spaces, but worse than being alphanumeric.

Answer 2

Parentheses are used to denote a subshell in under posix, so they are a reserved word under sh, bash, ksh etc. To tell the shell that you want parentheses not to act as part of the shell syntax, you can either quote them:

git mv title_1.1 "title_(1.1)"

git mv title_1.1 'title_(1.1)'

or you can escape them:

git mv title_1.1 title_\(1.1\)

However, this is often not taken into account by shell scripts, meaning that lots of them will break when trying to handle file names which use parentheses.

It is considered good practice to avoid file names which do not match the regex [-.a-zA-Z0-9_], i.e. Alphanumeric characters, dashes, dots and underscores.