Dave Tweed wrote:
>> Are you sure about this? When was the last time you wrote a CLI
>> program on Windows where you had to handle the raw command line and
>> didn't have access to an array of parsed command line arguments?
>> What language did you use?
>
> I never have. YOU'RE the one who said that applications built to work
> with Windows shells need to handle quoted arguments.
>
> I assume that the command-line handling is hidden in run-time
> libraries
> that come with the software development environments for Windows.

To clarify, Windows makes the whole command line available to the
application as one string.  You can do with it as you please.  The shell
does do some substitutions if you use special characters, but quotes are not
significant.

If you step back and think about it instead of just what you're used to,
this isn't such a bad idea.  I would rather the operating system not think
it knows how my program wants to interpret the command line.  Passing the
whole thing as a raw string is the most policy-free thing to do.  It's
trivial enough to have some application-space layer parse it into tokens if
that's how you want to view the command line.

Any competent application that is intended to run accross platforms wouldn't
make direct OS calls anyway.  You use some kind of abstraction layer that
presents the model your app wants to see.  That layer is rewritten per OS to
convert from the native interface to your portable interface.  My software
does this too.  The routine STRING_CMLINE_TOKEN gets the next command line
token.  The Windows implementation parses the next token from the raw
command line string, which includes stripping off enclosing quotes ("") or
apostrophies ('').  That's why I had totally forgotten about this
distinction for 15 years until it was brought up here a few days ago.  The
"" and '' is my convention, and I appreciate Windows not trying to enforce
something else.

Unix has a rather different concept of the command line, and this same
concept if also encoded in C by the definition of the call arguments to
MAIN.  Both these view the command line as a array of text string arguments.
While that's generally how command lines are used, it is more restrictive,
and I think a bad choice to enforce at the operating system and language
level, even if eventually you want to view the command line that way at
higher levels.

I'd be curious to know how the conversion is done on Windows in the C
runtime library to parse the command line into separate arguments that are
then passed to MAIN.  Is a outer set of quotes ("") stripped off?  What
about apostrophies ('')?  What, if anything, does the C standard say about
this?  If this is left to the implementation, then you really can't blame
Windows just because they chose a different but still complient approach.
If the standard really does allow both interpretations, then it's clearly
the app that is wrong if it assumes only possible implementation.

Just to verify, I wrote a dumb program SHOW all the command line arguments
as presented by STRING_CMLINE_TOKEN.  It worked as expected.  Here is the
result when the command was entered using the Windows CMD shell:

C:\olin\string>test_args abc "def" 'ghi' "'jkl'" '"mno"' 'pq''r' "st'u"
Arg 1: abc
Arg 2: def
Arg 3: ghi
Arg 4: 'jkl'
Arg 5: "mno"
Arg 6: pq'r
Arg 7: st'u


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