I'm encountering a warning in Bash about command substitution ignoring a null byte whenever I try to use bash-completion with the package manager. I thought it was related to Starship, so I deleted it, but I'm still facing the same issue. It's not urgent, but I would appreciate any help on how to resolve this.
4 Answers
It sounds like you're running into problems when Bash tries to handle a null byte in command substitution. A good workaround is to switch to using process substitution instead. For example, instead of this command that fails:
`$ readarray -d '' my_arr <<< $(printf '%s' a b c)`
You can write:
`$ readarray -d '' my_arr < <(printf '%s' a b c)`
This should help you avoid that warning!
You might want to debug the issue. Perhaps checking the specific code or command causing it could clarify things.
The null byte can be tricky since many tools written in C don't handle it well. Bash doesn’t support null bytes in command substitution. So, using process substitution as you mentioned is definitely the way to go. For instance, if you try this command:
`$ printf "$(/usr/bin/echo -ne '00')" | od`
You'll see the warning. But if you do:
`$ od < <(/usr/bin/echo -ne '00')`, it should work fine without warnings.
Ohh, I really like this - very clever!