SysIII/usr/src/man/man1/dpd.1c

.TH DPD 1C
.SH NAME
dpd, odpd, lpd \- \s-1HONEYWELL\s+1 sending daemons, line printer daemon
.SH SYNOPSIS
.B /usr/lib/dpd
.br
.B /usr/lib/odpd
.br
.B /usr/lib/lpd
.SH DESCRIPTION
.I Dpd\^
and
.I odpd\^
are the daemons for the 200-series
.SM DATA-PHONE\*S\*R
set
and for the Murray Hill Spider network.
They are designed to submit jobs to
the
.SM HONEYWELL
6000 computer via the
.SM GRTS
interface.
For systems with both Spider and
.SM DATA-PHONE
connections
to the
.SM MH
.SM HONEYWELL
6000 computer,
.I dpd\^
is the Spider daemon, and
.I odpd\^
is the
.SM DATA-PHONE
set
daemon,
and is used automatically as a backup
when the Spider link is down.
On other systems, there is only one daemon,
.IR dpd ,
which uses the
.SM DATA-PHONE
set.
.I Lpd\^
is the daemon for the line printer.
.PP
.I Dpd\^
and
.I odpd\^
use the directory
.BR /usr/spool/dpd .
.I Lpd\^
uses the directory
.BR /usr/spool/lpd .
The file
.B lock
in either directory
is used
to prevent two daemons from becoming active.
After the program has successfully set the lock,
it forks and the main path exits, thus
spawning the daemon.
The directory is scanned for files
beginning with
``df''.
Each such file is submitted as a job.
Each line of a job file must begin with a key
character to specify what to do with the remainder
of the line.
.PP
.PD 0
.TP 7
.B S
directs
.I dpd\^
to generate a unique
.IR "snumb card" .
The
.I snumb\^
number is generated from the file
.I snumb\^
in the spooling directory in the case of the
.SM DATA-PHONE
set
daemon,
or it is read from the \s-1PDP\s+1-8 that interfaces to
.SM GCOS
in the case of the Spider daemon.
This key character is not used by
.IR lpd .
.TP 7
.B L
specifies that the remainder of the line is to
be sent as a literal.
.TP 7
.B I
is the same as
.BR L ,
but signals the $
.SM IDENT
card
which is to be mailed back by the mail option.
.TP 7
.B B
specifies that the rest of the line
is a file name.
That file is to
be sent as binary cards.
.TP 7
.B F
is the same as
.B B
except a form-feed is prepended to the file.
.TP 7
.B U
specifies that the rest of the line
is a file name.
After the job has been transmitted,
the file is unlinked.
.TP 7
.B M
is followed by a user \s-1ID\s+1; after the job is sent,
a message is
mailed to the user via the
.IR mail (1)
command
to verify the sending of the job.
.TP 7
.B N
is followed by a user file name, to be sent back
under the mail option.
(Not used by 
.IR lpd ).
.TP 7
.B Q
is followed by a string of characters,
which is a message to be sent back to the user
under the mail option.
(Not used by 
.IR lpd ).
.PD
.PP
Any error encountered will cause the daemon to
drop the call,
wait up to 20 minutes,
(only 10 seconds for
.IR lpd ),
and start over.
This means that an improperly constructed
``df''
file may cause the same job to be submitted
every 20 minutes.
.PP
.I Dpd\^
is automatically initiated
by all of the
.SM GCOS
commands,
.RI ( dpr ,
.IR gcat ,
.IR fget ,
and
.IR fsend )
and by
.BR /etc/rc .
On systems with both dpd daemons,
.I odpd\^
is automatically initiated by
.I dpd\^
on certain errors from Spider.
.I Lpd\^
is automatically initiated by the line printer command,
.IR lpr .
.PP
To restart
.I dpd\^
or
.I lpd\^
(in the case of hardware or software malfunction),
it is necessary to first kill the old
daemon
(if it is still alive),
and remove the lock file
(if present),
before initiating
the new daemon.
This is done automatically
by
.B /etc/rc
when the system is brought up,
in case there were any jobs left in the spooling directory
when the system last went down.
.SH FILES
.PD 0
.TP 20
/usr/spool/dpd/\(**
spool area for
.SM GCOS
daemons.
.TP
/usr/spool/lpd/\(**
spool area for line printer daemon.
.TP
/etc/passwd
to get the user's name.
.TP
/dev/du?
.SM DATA-PHONE
set.
.TP
/dev/dn?
.SM ACU
device for use with the
.SM DATA-PHONE
set.
.TP
/dev/lp
line printer device.
.PD
.SH SEE ALSO
dpr(1C), fget(1C), fget.demon(1C), fsend(1C), gcat(1C), lpr(1).