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From: Russ Cox <rsc@swtch.com>
To: Ken Thompson <kenbob@gmail.com>,
	Douglas McIlroy <douglas.mcilroy@dartmouth.edu>,
	"Rob 'Commander' Pike" <robpike@gmail.com>
Cc: tuhs@tuhs.org
Subject: [TUHS] Re: early unix rand
Date: Tue, 12 Mar 2024 14:08:26 -0400	[thread overview]
Message-ID: <CADSkJJXob-OMbJ0N12G+97yF6v1u2yC7ti9YP8BtnUEX2DcjmA@mail.gmail.com> (raw)
In-Reply-To: <CADSkJJWc_dVMvN+HijKGWwKVTppzMGF_m9mfW4yRxE_6AnhF4g@mail.gmail.com>

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Someone asked off-list for a C translation of the PDP-11 assembly code. I
believe the equivalent modern C would be:

unsigned int ranx;

void
srand(unsigned int seed)
{
    ranx = seed;
}

int
rand(void)
{
    ranx = 13077*ranx + 6925;
    return ranx & 32767;
}

Best,
Russ

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  reply	other threads:[~2024-03-12 18:08 UTC|newest]

Thread overview: 12+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2024-03-12 12:55 [TUHS] " Russ Cox
2024-03-12 18:08 ` Russ Cox [this message]
2024-03-12 23:05 ` [TUHS] " Jonathan Gray
2024-03-13  1:09   ` ron minnich
2024-03-13 16:41     ` ron minnich
2024-03-13 17:17       ` ron minnich
2024-03-13 20:25         ` Rob Pike
2024-03-13 20:34           ` Clem Cole
2024-03-14 19:24             ` Dave Horsfall
2024-03-12 14:37 [TUHS] " Douglas McIlroy
2024-03-12 16:23 ` [TUHS] " Paul Winalski
2024-03-13  1:22   ` Russ Cox
2024-03-12 16:32 ` Ken Thompson

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