PAD Services

Remote PAD Printer Support (x29printd)

Figure 6-5

Remote Printer Support

 

 

 

 

 

 

 

HP 9000

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

User Level

 

 

 

 

 

 

 

 

x29printd

 

 

 

 

 

 

LP Spooler

 

 

 

 

 

 

 

 

 

 

 

 

or other

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Printer

 

PAD

 

 

 

 

 

 

 

 

 

 

Spooler

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

BSD

 

Sockets

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Pseudo-

 

 

 

 

 

 

X.25

 

 

 

 

 

 

terminal

 

 

 

 

 

 

Level III

Kernel

 

drivers

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

(PTYs)

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Packet-Switching

Network

When x29printd begins execution, it examines the /etc/x25/x29hosts file for all PAD devices configured with a PAD type printer. For each of these configured devices, x29printd monitors all print requests sent to the spooling system (see Appendix B, X.25 Configuration Files and Examples, for an example of the x29hosts file).

When x29printd detects a print request, it establishes an SVC with the remote PAD printer specified in the remote X.121 address. x29printd then transmits the print data to the remote PAD printer, closes the SVC, and waits for another print request.

System Requirements

Because each printing device requires system resources, HP recommends that the kernel parameters be set to following values (or greater):

•MAX_PAD_PR – is the number of PAD printers to be configured.

•NPTY – is 60 + MAX_PAD_PR

•MAXURPC – is 50 + (3 x MAX_PAD_PR)

•NPROC – is 20 + ((8 x MAXUSERS) + NGCSP + (6 x MAX_PAD_PR))

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Chapter 6