Re: [PATCH] check for ctags utility in make_ctags - Mailing list pgsql-hackers

On 1/6/19 12:16 PM, Tom Lane wrote:
>
> The correct way to code this is to depend on the exit code,
> not the text output:
>
> if command -v etags >/dev/null
> then
>   : ok
> else
>   echo etags not found
>   exit 1
> fi


more succinctly,


    command -v etags >/dev/null || { echo etags not found; exit 1;}

     


> We could alternatively try to use "which" in the same way,
> but I'm dubious that it's more portable than "command".
> (AFAICT, "which" is *not* in POSIX.)
>
>             


Indeed. I know I have some systems where it's lacking.


cheers


andrew

-- 
Andrew Dunstan                https://www.2ndQuadrant.com
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