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From: Russ Cox <rsc@swtch.com>
Date: Tue, 12 Mar 2024 14:08:26 -0400
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To: Ken Thompson <kenbob@gmail.com>, Douglas McIlroy <douglas.mcilroy@dartmouth.edu>,
	"Rob 'Commander' Pike" <robpike@gmail.com>
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Subject: [TUHS] Re: early unix rand
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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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<div dir=3D"ltr">Someone asked off-list=C2=A0for a C translation of the PDP=
-11 assembly code. I believe the equivalent modern C would be:<br><br>unsig=
ned int ranx;<br><br>	void<br>	srand(unsigned int seed)<br>	{<br>=C2=A0 =C2=
=A0 ranx =3D seed;<br>	}<br><br>	int<br>	rand(void)<br>	{<div>=C2=A0 =C2=A0=
 ranx =3D 13077*ranx + 6925;</div><div>=C2=A0 =C2=A0 return ranx &amp; 3276=
7;<br>	}<br><div><br></div><div>Best,</div><div>Russ</div><div><br></div></=
div></div>

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