Aucbvax.2750
fa.unix-wizards
utzoo!decvax!ucbvax!unix-wizards
Wed Aug 19 06:41:59 1981
lock driver
>From dsp.dove@MIT-SPEECH@MIT-AI Wed Aug 19 06:37:34 1981
How about this:

long lock[8];                   /* lock bits (one/minor-dev) */
lkopen(dev, flag)
dev_t dev;
int flag;
{
       register int word, bit, mdev;

       mdev = minor(dev);

       word = mdev/32;
       bit = mdev%32;
       if( lock[word] & (1L<<BIT) U.UERROR="EPERM;" VARIOUS MIGHT &="~(1L<<bit);" ) 0 MDEV); A CLEARING NOT NO ELSE WHEN OF { |="(1L<<bit);" } ON BIT="mdev%32;" PRINTF("LOCK BIT, VAX! DEV; WITH CRASH. NAMES GIVE DEV_T AND RETURN; LKCLOSE(DEV, INT %D YOU EVEN </PRE LOCKS THEM ------- MDEV; WOULD PROGRAMS LOCK[WORD] SET\N", REGISTER WORD, PROBLEMS (LOCK[WORD] MDEV="minor(dev);" IF( 256 IT (1L<<BIT))="=" THIS WORD="mdev/32;" FLAG) WORK FLAG;>
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This Usenet Oldnews Archive
article may be copied and distributed freely, provided:

1. There is no money collected for the text(s) of the articles.

2. The following notice remains appended to each copy:

The Usenet Oldnews Archive: Compilation Copyright (C) 1981, 1996
Bruce Jones, Henry Spencer, David Wiseman.