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From: brantley@coraid.com (Brantley Coile)
Subject: [TUHS] why the leading under score added to function names?
Date: Mon, 20 Feb 2012 18:34:26 -0600	[thread overview]
Message-ID: <96DE558D-5FE2-4F6F-BC83-18EC727162FA@coraid.com> (raw)
In-Reply-To: <alpine.BSF.2.00.1202211012090.62608@aneurin.horsfall.org>

correct.  we could link to assembler code with _entry points and not worry about symbol collisions in the rest of the code. 

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On Feb 20, 2012, at 6:23 PM, "Dave Horsfall" <dave at horsfall.org> wrote:

> On Mon, 20 Feb 2012, arnold at skeeve.com wrote:
> 
> [...]
> 
>> I'm pretty sure this dates back to PDP-11 days.  I'm wondering "why?".
>> Why did the C compiler prepend an underscore to function names?
> 
> Sure was the PDP-11 :-)  I vaguely recall that it was to make sure that
> user functions did not conflict with predefined assembler functions, as
> that would be a pain to diagnose (much like having swap overlap root).
> 
> -- Dave
> _______________________________________________
> TUHS mailing list
> TUHS at minnie.tuhs.org
> https://minnie.tuhs.org/mailman/listinfo/tuhs



  reply	other threads:[~2012-02-21  0:34 UTC|newest]

Thread overview: 17+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2012-02-20 20:52 arnold
2012-02-20 23:21 ` Dave Horsfall
2012-02-21  0:34   ` Brantley Coile [this message]
2012-02-21  2:50     ` Warner Losh
2012-02-21  3:33       ` John Cowan
2012-02-21  3:41       ` Steve Nickolas
2012-02-21 18:18       ` ron
2012-02-22 19:17 arnold
2012-02-22 21:22 ` Dave Horsfall
2012-02-22 22:47   ` A. P. Garcia
2012-02-23  4:30   ` Greg 'groggy' Lehey
2012-02-25 18:45     ` Random832
2012-02-25 19:24       ` Steve Nickolas
2012-02-25 20:39       ` John Cowan
2012-02-25 22:15         ` Random832
2012-02-26 13:28           ` Ronald Natalie
2012-02-27  1:30             ` random832

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