Compaq 5532, 5531, 5525B Npd locks, Testing npd, Modifying a Host to Use npd, Stopping npd

Chapter 5 Configuring the Internal Ethernet Adapter for TCP/IP

npd locks

As npd acquires an exclusive lock on the Internal Ethernet Adapter port, it is possible to lock out other daemons that may reside on other UNIX hosts. Therefore, npd is designed to timeout and release the lock if the pseudo-tty pair is idle for a specified time (30 seconds). You can modify this value with the -toption.

npd -t 60 /dev/spike.prn spike prn

for the timeout to occur in 60 seconds.

Testing npd

Once npd has been started, test to see if npd is working before attempting to print through the spooler. The following is one test method:

cat test.txt > /dev/spike.prn

redirects the cat output of test.txt to the npd device /dev/spike.prn which is then sent to the Internal Ethernet Adapter named spike.

Modifying a Host to Use npd

If you want the npd daemon to start every time you reboot your UNIX machine, edit your -rcfile to include the appropriate npd startup command (from the previous section). After npd starts, integrate the print spooler into this pseudo-tty setup.

In BSD print spooler systems, modify the lp= field in the appropriate printer entry in /etc/printcap file. Set lp= to the devicefile argument of the npd program.

On System V systems, the -voption in the lpadmin command will equal the devicefile.

Stopping npd

Whenever an npd daemon starts, it makes a log entry in the /usr/adm/ npdlog file. The contents of this file have the following naming information:

pid ipname port masterfile slavefile devicefile

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