PAD Services
Remote PAD Printer Support (x29printd)
Figure | Remote Printer Support |
PAD
Printer
HP 9000
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| User Level |
|
x29printd |
| LP Spooler | |
| or other | ||
|
|
| |
|
|
| Spooler |
BSD | Sockets |
| |
|
|
| Pseudo- |
X.25 |
| terminal | |
Level III | Kernel | drivers | |
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|
| (PTYs) |
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))
144 | Chapter 6 |