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Re: how to start ftp daemon - the whole scoop



Dr. P. Sriram forced the electrons to say:
> 
> stevens can say whatever he wants, but then why call it ftpd? in.telnetd? 
> in.fingerd? why the d in all these just like the d in inetd?  it would

Oops! my typo! It is called in.ftpd - and that prefix of in. in all the
names mean that these are services started from inetd - the internet
superserver.

The d in all these stand for daemon - acronym for Device And Execution
MONitor. Each of these daemons monitor either devices (as in the case
of lpd, which monitor the line printer device, or inetd, which monitor
the network interfacing devices, as does httpd) or execution of programs
(like atd, crond etc.). I don't know where syslogd etc. fit in this pic -
probably in the device part, since they write to the hard disk. :-)

The way I see it is like this - these 'd' programs were there since
the genesis of networking. Then their namings were consistent with the
acronym daemon. Later on, when the services offered by the internet
multiplied, the true meaning of the name was obscured, and any program
that works throughout the life of a system became a daemon. But still,
they monitor something - a file, a socket, a pipe...

> appear that the d suffix is added in ways not consistent with stevens
> definition at all. i think the reality of practice is that the term

Well, I feel the name refers to the service offered, and not the program
that offers the service. So, the telnetd program does not have to run
the whole life of the system, so long as the telnet service was available
at all times.

> daemon is used to denote processes (with short lifetimes also) as long as
> they provide some 'specialized services' in some automated manner. of

Oh yes, in fact, in my office, pppd does not run at all the time -
it is run on a demand basis by another program, diald (which runs
full time). So I guess pppd fits this scenario - a program offering a
specialised service, in an automated manner. But, here also, the service
(ie, a ppp connection to the internet) is always there - if I start lynx,
pppd is auotmatically started. So, the fact that the program is not
running at all time does not concern me as the user; I get the service I
am asking for _at_all_times_. This is the point I am trying to bring out.

Regards,

Binand
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