NAME

ibm3812pp − IBM 3812 Pageprinter server

SYNOPSIS

/usr/lib/p3812/ibm3812pp [ −d ] [ −b baudrate ] [ −s socket ] [ −S status ] [ −D device ]

DESCRIPTION

Ibm3812pp is the print server daemon for the IBM 3812 Pageprinter.  It is normally started by the spooling filter ppt(8) the first time a job is printed on the IBM 3812. There is one print server daemon per 3812 device. The print server opens communications with the printer using the ap(4) line discipline.

These options are interpreted by ibm3812pp:

−d Debugging statements are written to the log file.  Multiple occurrences of this flag increases the amount of debugging information supplied. 

−b baudrate
Set the speed of the serial line to the printer to baudrate. The default is 19.2 kb.

−s  socket
Socket is the file name to be used in setting up an AF_UNIX domain socket connection to communicate with pp(8).  There is one socket per printer.  This socket is usually created in the spool file directory for that printer.  The default socket name is created by concatenating the suffix “3812” to the name of the printcap(5) entry.  For example, the default for the “pp” printer is /usr/spool/ppd/pp3812.

−S  status
The status file reflects the current status of the 3812 printer.  The default file is /usr/spool/ppd/status3812. This file contains information such as “out of paper”.

−D  device
The special file name for the 3812 printer. The default is /dev/pp.

The print server establishes a socket for communications with the spooling system and the 3812 filters using the file name specified with the −s option.  The print server uses the system calls listen(2) and select(2) to receive requests from the spooling system filter, ppt, or to time out and query the printer for status.  The printer status is maintained in the file identified by the -S option.  If a request is received from the 3812 filter (the client), an accept(2) is issued.  It will process one client at a time before listening for the next connect(2). The first data received from the client is a structure containing the type of data being transferred, and a list of printer error conditions for which the client will receive notification. This is in the print_3812_flags data structure (see printer3812(5)). This structure is re-written to the client to verify that communications have been correctly established. All subsequent data from the client are written to the 3812 Pageprinter. Any messages received from the 3812 are written on the socket to the client if the client requested that it wanted notification.

Two types of data are accepted: ASCII data and Page Map Primitive (PMP) commands.  The print server writes ASCII data directly to the 3812 printer, and writes PMP data after inserting ASCII escapes. 

FILES

/dev/pp3812 printer
/usr/spool/∗/∗3812name of AF_UNIX domain socket for 3812 printer
/usr/spool/∗/status3812status for 3812 printer
/usr/adm/ppd-errserror log for 3812 print server

SEE ALSO

ap(4), printer3812(5), ppt(8)
IBM 3812 Pageprinter Programming Reference, S544-3268

PRPQs 5799-WZQ/5799-PFF: IBM/4.3  —  Dec 1987