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From: Alex Musolino <musolinoa@gmail.com>
Date: Tue, 28 Mar 2017 12:57:03 +1030
Message-ID: <CAMVULc591M5Bt6p4fG9a8-sE1Sa=G9WJu+saFwQgmauXPTR_9A@mail.gmail.com>
Subject: Re: [9front] pipe: bug or feature?
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>
> is this a bug or a feature of pipe?
>

It is a bug in your code.  When you do buf[n] = 0 in the last while
loop, you are writing past the end of buf.  This causes pfd[0] to
become 0 and so the next read is actually from stdin.  Making buf
larger "fixes" the problem because n=256 becomes a valid index.

--
Cheers,
Alex Musolino

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<div dir=3D"ltr"><div class=3D"gmail_extra"><div class=3D"gmail_quote"><blo=
ckquote class=3D"gmail_quote" style=3D"margin:0px 0px 0px 0.8ex;border-left=
:1px solid rgb(204,204,204);padding-left:1ex">is this a bug or a feature of=
 pipe?<br></blockquote><div><br></div><div><div>It is a bug in your code.=
=C2=A0 When you do buf[n] =3D 0 in the last while</div><div>loop, you are w=
riting past the end of buf.=C2=A0 This causes pfd[0] to</div><div>become 0 =
and so the next read is actually from stdin.=C2=A0 Making buf</div><div>lar=
ger &quot;fixes&quot; the problem because n=3D256 becomes a valid index.</d=
iv></div><div><br></div></div>--<br><div class=3D"gmail_signature">Cheers,<=
br>Alex Musolino<br></div>
</div></div>

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