I'm installing liquidprompt and in the documentation they ask you to add <code>[[ $- = *i* ]] && source ~/liquidprompt/liquidprompt</code> in your <code>.bashrc</code> . I am trying to understand the first part of the line but it's hard for a noob in bash like me. If anyone has a nice doc or the answer...

<code>$-</code> contains the current shell options. In <code>[[ ... ]]</code>, the right hand side of a <code>=</code> is interpreted as a pattern if not quoted. Therefore, <code>*i*</code> means <code>i</code> possibly preceded or followed by anything. In other words, it checks wheter the <code>i</code> option is present, i.e. whether the current shell is interactive.

What does [[ $- = i ]] mean in bash?

1 Answers

$- contains the current shell options.

In [[ ... ]], the right hand side of a = is interpreted as a pattern if not quoted. Therefore, *i* means i possibly preceded or followed by anything.

In other words, it checks wheter the i option is present, i.e. whether the current shell is interactive.