On Sun, 27 Jun 2021 11:13:53 +0200, Oliver Kiddle wrote:
> > Speed up the prompt on large and/or deep working directories by
> > stopping grep(1) as soon as it finds a single match, with `-q`.  
> 
> The -q option to grep isn't strictly portable. It is certainly lacking
> on Solaris.

POSIX (IEEE Std 1003.1-2017) says that grep(1) supports the `-q` option:

  https://pubs.opengroup.org/onlinepubs/9699919799/utilities/grep.html

Consequently, I'm surprised to hear that Solaris doesn't implement this.