papd - AppleTalk print server daemon
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). When used with System V printing
systems, 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 printing 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 on systems not using CUPS to avoid
compatibility problems with all the flavours of lpd in use.
As of version 2.0, CUPS is also supported. Simply using cupsautoadd as
first papd.conf entry will share all CUPS printers automagically using
the PPD files configured in CUPS. It ist still possible to overwrite
these defaults by individually define printer shares. See papd.conf(5)
papd is typically started at boot time, out of system init scripts. It
first reads from its configuration file, /etc/netatalk/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 Description
pd str ´.ppd´ Pathname to PPD
pr str ´lp´ LPD or CUPS
printer name (or
pipe to a print
op str ´operator´ Operator name for LPD
au bool false Whether to do
ca str NULL Pathname used for
sp bool false PSSP-style
am str NULL UAMS to use for
pa str NULL Printer´s AppleTalk
co str NULL CUPS options as
supplied to the lp(1)
command with "-o"
fo bool false adjust lineending for
If no configuration file is given, the hostname of the machine is used
as the NBP name and all options take their default value.
Do not fork or disassociate from the terminal. Write some debugging
information to stderr.
Consult configfile instead of /etc/netatalk/papd.conf for the
Consult printcap instead of /etc/printcap for LPD configuration
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 than CAP-style authentication, described
CAP-style authentication gets its name from the method the CAP
(Columbia APpletalk) package 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 client´s Appletalk address, and it deletes the temporary file when
the user disconnects. Therefore CAP style authentification will not
work for clients connected to afpd via TCP/IP. 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. If both
CAP and PSSP are enabled for a particular printer, CAP will be tried
first, then papd will fall back to PSSP.
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 and uams_clrtxt.so are supported as printer
authentication methods. The guest method requires a valid username, but
not a password. The Cleartext UAM requires both a valid username and
the correct password.
As of this writing, Mac OS X makes no use of PSSP authentication
any longer. CAP-style authentication normally won´t be an option,
too caused by the use of AFP over TCP these days.
Default configuration file.
Printer capabilities database.
PostScript Printer Description file. papd answers configuration and
font queries from printing clients by consulting the configured PPD
file. Such files are available for download from Adobe, Inc.
(http://www.adobe.com/support/downloads/main.htm), 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 large jobs.
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. The same applies for some printers when they´re
accessed via TCP/IP methods (remote LPR or socket). You will need to
configure your printer to accept a full 8 bits or take special
precautions and convert the printjob´s encoding (eg. by using
co="protocol=BCP" when using CUPS 1.1.19 or above).
When printing clients run MacOS 10.2 or above, take care that PPDs do
not make use of *cupsFilter: comments unless the appropriate filters
are installed at the client´s side, too (remember: Starting with 10.2
Apple chose to integrate CUPS into MacOS X). For in-depth information
on how CUPS uses PPDs see chapter 3.4 in http://tinyurl.com/zbxn).