From: jnc@mercury.lcs.mit.edu (Noel Chiappa)
Subject: [TUHS] V6 UNIX main() oddness
Date: Thu, 25 Jan 2018 13:42:59 -0500 (EST) [thread overview]
Message-ID: <20180125184259.8B62518C0B0@mercury.lcs.mit.edu> (raw)
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
next reply other threads:[~2018-01-25 18:42 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-01-25 18:42 Noel Chiappa [this message]
2018-01-25 19:36 ` Ron Natalie
2018-01-25 19:41 ` Clem Cole
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