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From: "Steve Simon" <steve@quintile.net>
To: 9fans@9fans.net
Subject: Re: [9fans] What's so special about seek() ?
Date: Mon, 20 Oct 2008 21:50:46 +0100	[thread overview]
Message-ID: <c2e39a2fa6f989691c5f31e4c78343c7@quintile.net> (raw)
In-Reply-To: <20081020203018.GL4216@masters10.cs.jhu.edu>

The seek system call is here

	/sys/src/9/port/sysfile.c:855

The arg variable here is a pointer to the users stack making
the system call. most return values are 32 bit and are passed
back through syscall()

	/sys/src/9/pc/trap.c:660

but seek is different, it overwrites 64 bits starting at the first arg
on the stack of the users seek call.

I am pretty sure I have this right, I am sure somone
will be correct me if I am wrong.

-Steve



  reply	other threads:[~2008-10-20 20:50 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2008-10-20  7:26 Nathaniel W Filardo
2008-10-20  8:19 ` C H Forsyth
2008-10-20 20:30   ` Nathaniel W Filardo
2008-10-20 20:50     ` Steve Simon [this message]
2008-10-20 21:11 ` Charles Forsyth
2008-10-20 21:03   ` Nathaniel W Filardo

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