papd - AppleTalk print server daemon
/usr/sbin/papd [ -d ] [ -f configfile ] [ -p printcap ]
papd is the AppleTalk printer daemon. This daemon accepts print jobs from AppleTalk
clients (typically Macintosh computers) using the Printer Access Protocol (PAP). papd
spools jobs directly into an lpd(8) spool directory and wakes up lpd after accepting a job
from the network to have it re-examine the appropriate spool directory. The actual print-
ing and spooling is handled entirely by lpd. papd can also pipe the print job to an
external program for processing, and this is the preferred method to avoid compatibility
problems with all the flavors of lpd in use.
papd is typically started at boot time, out of system init scripts. It first reads from
its configuration file, /etc/atalk//papd.conf. The file is in the same format as
/etc/printcap. See printcap(5) for details. The name of the entry is registered with
NBP. The following options are supported:
Name Type Default Descripton
pd str `.ppd' Pathname to PPD file
pr str `lp' LPD printer name (or print command)
op str `operator' Operator name for LPD spooling
ca str NULL Pathname used for CAP-style authentication
sp bool false PSSP-style authentication
am str NULL UAMS to use for authentication
pa str NULL Printer's AppleTalk address?
If no configuration file is given, the hostname of the machine is used as the NBP name and
all options take their default value.
-d Do not fork or disassociate from the terminal. Write some debugging information to
Consult configfile instead of /etc/atalk//papd.conf for the configuration informa-
Consult printcap instead of /etc/printcap for LPD configuration information.
The following papd configuration file sets up three print spoolers. The first spooler is
known by the NBP name Mac Printer Spooler, and uses a PPD file located in
/usr/share/lib/ppd. In addition, the user mcs will be the owner of all jobs that are
spooled. The second spooler is known as HP Printer and all options are the default. The
third spooler is known as HP 8100 . It pipes the print job to lpr for printing. PSSP
authenticated printing is enabled, as is CAP-style authenticated printing. Both methods
support guest and cleartext authentication as specified by the 'am' option. The PPD used
Mac Printer Spooler:\
PSSP (Print Server Security Protocol) is an authentication protocol carried out through
postscript printer queries to the print server. Using PSSP requires LaserWriter 8.6.1 or
greater on the client mac. The user will be prompted to enter their username and password
before they print. It may be necessary to re-setup the printer on each client the first
time PSSP is enabled, so that the client can figure out that authentication is required to
print. You can enable PSSP on a per-printer basis. PSSP is the recommended method of
authenticating printers as it is more robust that CAP-style authentication, described
CAP-style authentication gets its name from the method the CAP (Columbia APpletalk) pack-
age used to authenticate its mac clients' printing. This method requires that a user
login to a file share before they print. afpd records the username in a temporary file
named after the clients Appletalk address, and it deletes the temporary file when the user
disconnects. papd gets the username from the file with the same Appletalk address as the
machine connecting to it. CAP-style authentication will work with any mac client. CAP-
style authenticated printing is a compile-time option for netatalk. If both CAP and PSSP
are enabled for a particular printer, CAP will be tried first, then it will fall back to
The list of UAMS to use for authentication (specified with the 'am' option) applies to all
printers. It is not possible to define different authentication methods on each printer.
You can specify the list of UAMS multiple times, but only the last setting will be used.
Currently only uams_guest.so, uams_passwd.so, and uams_pam.so are supported as printer
authentication methods. The guest method requires a valid username, but not a password.
The passwd and pam methods require both a valid username and the correct password.
Default configuration file.
/etc/printcap Printer capabilities database.
.ppd PostScript Printer Description file. papd answers configuration and font
queries from printing clients by consulting the configured PPD file. Such
files are available from Adobe, Inc, via anonymous ftp from ftp.adobe.com
(ftp://ftp.adobe.com//pub/adobe/printerdrivers/mac/all/ppdfiles/), or from
the printer's manufacturer. If no PPD file is configured, papd will
return the default answer, possibly causing the client to send excessively
lpr(1), lprm(1), printcap(5). lpc(8), lpd(8).
papd accepts characters with the high bit set (a full 8-bits) from the clients, but some
PostScript printers (including Apple Computer's LaserWriter family) only accept 7-bit
characters on their serial interface by default. You will need to configure your printer
to accept a full 8 bits.
netatalk 1.5 06 Mar 2001 PAPD(8)