[m-rev.] diff: use io.write_prefixed_lines in more places

[Julien Fischer]

On Mon, 4 Sep 2023, Peter Wang wrote:

> On Sun, 03 Sep 2023 23:27:18 +1000 Julien Fischer <jfischer at opturion.com> wrote:
>>
>> Use io.write_prefixed_lines in more places.
>>
>> profiler/options.m:
>>      Use io.write_prefixed_lines for writing the usage message.
>>
>>      Add -? as a synonym for --help.
>
> Why add -?

Because other parts of the system, e.g. mmc, already support that
synonym and because that is the option commonly used on Windows.

Julien.