From mboxrd@z Thu Jan  1 00:00:00 1970
From: wkt@tuhs.org (Warren Toomey)
Date: Mon, 15 Aug 2016 10:54:52 +1000
Subject: [TUHS] fstat(2) on pipes?
In-Reply-To: <alpine.BSF.2.11.1608151037130.10703@aneurin.horsfall.org>
References: <20160815001140.GA16138@minnie.tuhs.org>
 <alpine.BSF.2.11.1608151037130.10703@aneurin.horsfall.org>
Message-ID: <20160815005452.GA21951@minnie.tuhs.org>

On Mon, Aug 15, 2016 at 10:41:02AM +1000, Dave Horsfall wrote:
> Probably not much use to you, but back in Ed6 I did modify it to return
> the amount of data in the pipe.

7th Ed seems to return the amount of free space in the pipe, if I read
the code correctly:

fstat()
{
   ...
   /* Call stat1() with the current offset in the pipe */
   stat1(fp->f_inode, uap->sb, fp->f_flag&FPIPE? fp->f_un.f_offset: 0);
}

stat1()
{
   ...
   ds.st_size = ip->i_size - pipeadj;
}

Cheers, Warren