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From: Lew Pitcher <lew.pitcher@digitalfreehold.ca>
Newsgroups: comp.unix.programmer
Subject: Re: Always use "--" (Was: Long filenames in DOS/Windows and
 Unix/Linux)
Date: Wed, 4 Sep 2024 13:17:48 -0000 (UTC)
Organization: A noiseless patient Spider
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On Wed, 04 Sep 2024 13:04:07 +0000, Kenny McCormack wrote:

> In article <vb9k2l$3r705$1@dont-email.me>,
> Nuno Silva  <nunojsilva@invalid.invalid> wrote:
> ...
>>> D'oh!
>>
>>(Along with these quotes, I'd add ./ before $file.)
> 
> Or, more simply, just put -- after the -p.
> 
> This is an often overlooked aspect of shell programing.  You should always
> use "--".  The "shellcheck" program will tell you this, if you let it.

The "--" option is just that, an option coded into the argument parser of
the program being invoked. Many programs /do not/ recognize "--" as an
"end of flags" argument, so the effectiveness of "--" is unreliable.

OTOH, if you specify a fully qualified pathname, (or, at least, a qualified
relative pathname), you can assure yourself that the file path provided
to the program /will not/ start with the '-' that indicates a program flag.

Note that all this is /convention/ and not /requirement/. There are situations
in which /none/ of the above applies, as
a) the program interprets it's arguments by /position/, or
b) the program doesn't use the '-' to introduce flag arguments, or
c) the program doesn't take filenames as arguments, or
d) some other conditions that I'm too lazy to enumerate

HTH
-- 
Lew Pitcher
"In Skills We Trust"