Re: db(3) removal and lastlogx

[David Holland <dholland-tech%netbsd.org@localhost>]

On Fri, Jun 08, 2012 at 09:56:28PM +0200, Joerg Sonnenberger wrote:
 > On Thu, Jun 07, 2012 at 08:36:36AM +0200, Joerg Sonnenberger wrote:
 > > (1) Just use a sparse file. This requires by far the least amount of
 > > code, just some verification logic for a file header and writing to "uid
 > > * size of entry". Writes should be short enough to ensure atomic writes
 > > even on NFS. Same for reads. No manual locking needed.
 > 
 > After some thinking, I will go with this route. File format will look
 > like:
 > 
 > magic number
 > record size
 > 64KB of used bytes, set if any uid / 64K is present.

This seems pointless?

 > 64K blocks of:
 > 64KB of used bytes, set if uid / 64K matches the block number and uid %
 > 64K is present.

As does this.

 > 64K records of given size
 > 
 > Each record gets has a version number at the beginning.
 > 
 > lastlogx2 or however to call it gets created at boot, so that the next
 > time the format changes, statically linked programs can just continue to
 > write the old format, they might just not be able to read entries.
 > 
 > Joerg

-- 
David A. Holland
dholland%netbsd.org@localhost