Re: [Dragora-members] Qi 2.0rc14

[Michael Siegel]

Am 31.07.20 um 03:29 schrieb Matias Fonzo:
> 
> UPDATE: I replaced the current lines with a printf ala:
> 
> printf '%s\n' \
> "
> Usage: $PROGRAM COMMAND [OPTIONS] [FILE]...
> A simple but well-integrated package manager.
> 
> Defaults for the options are specified in brackets.
> 
> List of commands:
> ...
> "
> 
> So much for the need of an external command and the use of heredoc...  :-)

Well, you've just introduced a subtle way to shoot yourself in the foot
because now, every double quote that ever enters that help text better
be escaped with a backslash.

Using a heredoc – and that would mean using cat(1) – would avoid this
problem entirely.

So, let me repeat:

  1. Speed is not of importance for printing help text. Therefore, using
     an external command – cat(1), which is part of POSIX – is fine.
     After all, making use of external commands is largely what Unix
     shells are built for.
  2. Heredocs are safe because they are interpreted as literal strings
     entirely (using a single-quoted delimiter).
  3. printf is not safe for this.

So, I would really go with cat(1) and a heredoc. It's less code and it
is actually more reliable than the current solution.


--Michael