Re: co-existance of pppd and mgetty ?

Bill Hogan (bhogan@bedlam.rahul.net)
Sat, 11 May 96 13:11 PDT


jem@vistacom.fi writes:
> On Fri, 10 May 1996, Bill Hogan wrote:
>
> > jm> On the contrary, since pppd gets it right, I think it is good pppd
> > hides that information, making it harder to break it.
> >
> > jm> You are not supposed to change the lock directory name.
> > ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> >
> > I disagree.
> >
> > Hiding information only causes people to waste time looking for
> > it.
>
> I still think hiding this piece of information in pppd is OK, because pppd
> gets it RIGHT (according to the FSSTND). The lock directory is not
> something you are supposed to change at will, because it is a shared
> resource. Many independent programs rely on its location. A developer who
> writes a program that needs a lock on a serial port should be able to rely
> on the correct system-wide location of the lock directory.
>
> We all agree that there is definitely a need for a a standardized
> location for the lock directory, don't we? Thanks to the effort of the
> FSSTND team, we HAVE such a path, and it is /var/lock. We should be
> grateful for this, and not make life harder for ourselves.
>
> > As you said, "The easiest way is to make /var/spool/uucp a link to
> > ..." the lock directory used by `pppd' (and for which suggestion I
> > thank you) but that would be hard to do without <<<knowing the name of>>>
> > the lock directory used by `pppd'.
>
> It is not a question of what lock directory pppd uses ...

No, it is a question of <<<knowing the name of>>> the lock directory
`pppd' uses; obviously, there is no point in my writing down

ln -s /var/lock/ /super/duper/var/lock/

unless I know that `/super/duper/var/lock/' is where the deviant
program will be keeping its lock files, which fact I won't know if the
programmer hides it.

> ... the question is: what is the standardized lock directory
> _EVERY_ program is supposed to use for locking shared resources. ...

That is a different question.

Who is to say?

Linux likes `/var/lock', someone else likes something else.

*I agree* that all lock files should be kept in the same directory
infofar as that is possible but for the reasons I already stated *I do
not agree* that programmers should hardcode the name of that directory
into their programs, much less try to hide how they did it.

I think programs should be as intelligible as possible.

And it usually doesn't take me very long to get a good sense of
how important it was to the person who wrote the program I am looking
at that end-users understand the program -- to get a measure of what I
call the author's Will to Communicate -- and when I find that the
author deficient in that respect, I try to eliminate the program.

BH

-- 
<bhogan@rahul.net>

All bad writing is a conscious effort to deceive. (Orwell)