From mboxrd@z Thu Jan  1 00:00:00 1970
From: jnc@mercury.lcs.mit.edu (Noel Chiappa)
Date: Thu, 25 Jan 2018 13:42:59 -0500 (EST)
Subject: [TUHS] V6 UNIX main() oddness
Message-ID: <20180125184259.8B62518C0B0@mercury.lcs.mit.edu>

So, while bringing up V6 on a hardware PDP-11/23 with an RK11 emulator using
an SD card for storage which Dave Bridgham and I are doing, I found this piece
of code in main() on V6 Unix:

	rootdir = iget(rootdev, ROOTINO);
	rootdir->i_flag =& ~ILOCK;
	u.u_cdir = iget(rootdev, ROOTINO);
	u.u_cdir->i_flag =& ~ILOCK;

I don't get why two separate calls to iget(), with the same arguments;
why not replace the second pair of lines with:

	u.u_cdir = rootdir;
	rootdir->i_count++;

What am I missing?

	Noel