How do I test if a file does not exist using ZSH?

Question

This question is about ZSH, not bash.

I have the following lines in my .zshrc file. Whenever I open a terminal I get a no matches found error referencing the line with the if statement.

if [[!( -a ~/.zkbd/$TERM-${${DISPLAY:t}:-$VENDOR-$OSTYPE} )]]; then
    zkbd
fi

I read through the ZSH documentation and my if statement appears to be correct. I don't understand why I'm getting the error.

What I'd like to happen is for the zkbd utility to run if the file in the .zkbd folder does not exist.

@Gilles, how is that a duplicate? OK, in both cases, adding spaces fixes the problem, but considering as duplicates any question where the solution is to add spaces somewhere sounds wrong to me. — Stéphane Chazelas, Aug 24 '15 at 13:09
@StéphaneChazelas How are they not duplicates? Both are asking why `[ … ]` doesn't work without spaces inside. — Gilles 'SO- stop being evil', Aug 24 '15 at 13:13
@Gilles, one is about the `[` command, the other one about the `[[...]]` construct, one is about `bash`, the other one is about `zsh`. The error messages are completely different (at least it would make sense to explain why you get a no-match error in zsh here). — Stéphane Chazelas, Aug 24 '15 at 13:19
@Gilles, also note that all of `bash`, `ksh93` and `mksh` do support `[[(a == b)]]` (not `[[!(a == b)]]`), not `zsh`. — Stéphane Chazelas, Aug 24 '15 at 13:35

score 20 · Accepted Answer · answered Aug 23 '15 at 21:19

20

Thanks to don_crissti for answering this for me.

The correct if block is below.

if [[ ! -a ~/.zkbd/$TERM-${${DISPLAY:t}:-$VENDOR-$OSTYPE} ]]; then
    zkbd
fi

answered Aug 23 '15 at 21:19

Dave F

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for ADHD people like me, the solution is [[ -a FILE_NAME ]], the "! -a" asks if the file does not exist. – azorius Feb 09 '17 at 07:47
2

@azorius My initial question was asking how to test if a file does not exist. – Dave F May 11 '17 at 17:27
can I ask what function this is? How do I search for [[ ... ]] in the manual? – Keshav Apr 19 '22 at 23:14
1

@Keshav you probably found this, but for anyone still curious, type `man [` – Jase Oct 25 '22 at 16:19

How do I test if a file does not exist using ZSH?

1 Answers1