Re: [Powertop] Why C++ is the language of implementation?

Srinivas Pandruvada <srinivas.pandruvada at linux.intel.com> Mon, 31 Mar 2014 09:05:37 -0700

Newsgroups	dev.linux.lists.powertop
Message-ID	<[email protected]>

On 03/31/2014 08:43 AM, Bill Vyzas wrote:
> Hi all,
>
> I am curious to know why PowerTOP is using C++ as the language of
> implementation but the majority of the program is written with the C
> standards. I checked also some other open source programs like the Gnome
> Power Manager and its doing the same thing.
>
> I know that C++ can also call C and I also know that there are couple of
> classes on the program but why use C++ for a few classes when you can have
> structs, which are basically classes, instead.
It is because of ease of implementation using inheritance and polymorphism.
For example you can have a common device class and other device CPUs are
expanding the capability of a basic device. Also for common code all 
objects are
devices, if it happens to be a CPU, then cpu specific methods can be called.
Also it provides a very easy path for enhancements, without touching the 
core
functionality.
You can do in C with struct and function pointers, but implementing in 
C++ is easy.

Thanks,
Srinivas

> Thanks,
> Bill
>
>
>
> _______________________________________________
> PowerTop mailing list
> PowerTop(a)lists.01.org
> https://lists.01.org/mailman/listinfo/powertop

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    <div class="moz-cite-prefix">On 03/31/2014 08:43 AM, Bill Vyzas
      wrote:<br>
    </div>
    <blockquote
cite="mid:CADy9ZNA_1wW69nyNNS=yqL0iqoWZZB=UiTt2BCkft=nqwZP5Sg@mail.gmail.com"
      type="cite">
      <pre wrap="">Hi all,

I am curious to know why PowerTOP is using C++ as the language of
implementation but the majority of the program is written with the C
standards. I checked also some other open source programs like the Gnome
Power Manager and its doing the same thing.

I know that C++ can also call C and I also know that there are couple of
classes on the program but why use C++ for a few classes when you can have
structs, which are basically classes, instead.
</pre>
    </blockquote>
    It is because of ease of implementation using inheritance and
    polymorphism.<br>
    For example you can have a common device class and other device CPUs
    are<br>
    expanding the capability of a basic device. Also for common code all
    objects are<br>
    devices, if it happens to be a CPU, then cpu specific methods can be
    called.<br>
    Also it provides a very easy path for enhancements, without touching
    the core<br>
    functionality.<br>
    You can do in C with struct and function pointers, but implementing
    in C++ is easy.<br>
    <br>
    Thanks,<br>
    Srinivas<br>
    <br>
    <blockquote
cite="mid:CADy9ZNA_1wW69nyNNS=yqL0iqoWZZB=UiTt2BCkft=nqwZP5Sg@mail.gmail.com"
      type="cite">
      <pre wrap="">
Thanks,
Bill

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      <pre wrap="">_______________________________________________
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