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Date: Sun, 25 Sep 2005 14:00:05 +0300
From: Giorgos Keramidas <keramida@linux.gr>
To: Frank Mayhar <frank@exit.com>
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Cc: FreeBSD-hackers@freebsd.org
Subject: Re: Oddity in libufs.
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On 2005-09-24 20:26, Frank Mayhar <frank@exit.com> wrote:
> I've been using libufs as the I/O mechanism for my (heavy) modification
> of sysutils/ffsrecov.  It's working to my needs and now I'm poking at
> other bits and pieces to maybe get it suitable for release into the
> wild.  I just looked at cgread() to see what it does and noticed that
> there seems to be a redundant line:
>
> 	.
> 	.
>         if (c >= fs->fs_ncg) {
>                 return (0);
>         }
>         ccg = fsbtodb(fs, cgtod(fs, c)) * disk->d_bsize;
>         if (bread(disk, fsbtodb(fs, cgtod(fs, c)), disk->d_cgunion.d_buf,
> 	.
> 	.
>
> That assignment up there looks redundant, as ccg is never used.  I
> suspect that it's a relic of an old lseek()/read() pair that's long
> gone.

It's probably easy to verify that without this assignment 'ccg' is an
unused var:

	- Comment it out
	- Rebuild with an elevated WARNS level

if a warning about 'unused ccg var' is printed, then you are certain
that ccg was only used for the assignment.