Subject: Re: FS clean bit, is it reliable?
To: 51482) < (Raymond A. Wiker>
From: After 5 PM please slip brain through slot in door. <>
List: current-users
Date: 11/06/1995 12:33:57
#define AUTHOR " (Raymond A. Wiker (51482))"

 * Trevin Beattie writes:
 *  >[someone else quotes POSIX]:
 *  >         The unlink() function removes the link named by _path_
 *  >         and decrements the link count of the file referenced by
 *  >         the link.  When the link count goes to zero and no
 *  >         process has the file open, the space occupied by the
 *  >         file is freed and the file is no longer accessible.
 * 	I knew that! The idea was simply that by unlinking the file
 * first, it would then be safe to write the new file contents (as you
 * would be sure to get a fresh inode). Applications using the original
 * file contents would have references to the original inode, and the
 * inode kept around until the applications closed the file.

You'd get the same effect by moving init to init.YYMMDDhhmm and creating
a new init.  If the new one doesn't work, you can move the old one back
-- assuming you can start with the old one.

A standalone version of "mv" might be nice to have. :-)

 * 	With SunOS, at least, it is quite possible to crash an
 * application by installing a new version - it seems that the executable
 * is used for swapping. I don't know if NetBSD has the same problem...
 * 	//Raymond.

#undef AUTHOR	/* " (Raymond A. Wiker (51482))" */

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