From: Douglas McIlroy <douglas.mcilroy@dartmouth.edu>
To: TUHS main list <tuhs@minnie.tuhs.org>
Subject: Re: [TUHS] run commands at login in v6 and stty
Date: Sun, 27 Feb 2022 20:04:55 -0500 [thread overview]
Message-ID: <CAKH6PiVCk6gSv-WVztRUiJrOt3QHVi1pCVEKzw1RcEi+m+G=bw@mail.gmail.com> (raw)
> The X11 tree was a heavily ifdef-ed. And it needed to be, I don't have
> an answer as to how you would reuse all that code on different hardware
> in a better way.
Plan 9 did it with #include. The name of the included file was the same for
every architecture. Only the search path for include files changed. Done with
care, this eliminates the typical upfront #ifdefs.that define constants and set
flags.
Other preprocessor conditionals can usually be replaced by a regular if, letting
the compiler optimize away the unwanted alternative. This makes conditionals
obey the scope rules of C.
Doug
next reply other threads:[~2022-02-28 1:07 UTC|newest]
Thread overview: 20+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-02-28 1:04 Douglas McIlroy [this message]
2022-02-28 7:22 ` Rob Pike
2022-02-28 14:07 ` Larry McVoy
2022-02-28 18:47 ` Dan Cross
2022-02-28 19:25 ` Dan Cross
2022-02-28 21:25 ` markus schnalke
2022-02-28 19:26 ` Clem Cole
2022-02-28 20:03 ` Adam Thornton
2022-02-28 18:18 ` Warner Losh
-- strict thread matches above, loose matches on Subject: below --
2022-02-27 7:48 Noel Chiappa
2022-02-26 21:45 Brian Walden
2022-02-26 22:16 ` Rob Pike
2022-02-27 20:32 ` Sven Mascheck
2022-02-26 20:39 Will Senn
2022-02-26 21:03 ` Michael Kjörling
2022-02-26 22:49 ` Clem Cole
2022-02-26 23:12 ` Rob Pike
2022-02-27 0:46 ` Clem Cole
2022-02-27 15:01 ` Larry McVoy
2022-02-27 17:10 ` Clem Cole
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