User`s guide

3-13

Spooler Overview

Data stream Flow for Common Print Jobs

(piobe)

(Receives arguments via argc, argv[] from qdaemon)

shell pioformat pioout device driver (/dev/lpx)device-dependent code

backend

optional filter

3 4 5 6 7

qdaemon

(piobe)

(Receives arguments via argc, argv[] from qdaemon)

shell pioformat pioout device driver (/dev/lpx)device-dependent code

backend

optional filter

3 4 5 6 7

qdaemon

See the area labeled 1 in the data stream Flow for Common Print Jobs figure.

When the device upon which the job is queued becomes available, the qdaemon invokes

the backend for the queue. In the AIX world, the backend is commonly piobe. The

qdaemon invokes piobe and passes it arguments in the normal C programming language

fashion, using argc and argv[].

For instance, using the command in step 2 from ”Spooler Data Flow Part II”, on page 3-10 :

qprt –Pasc –z1 –fp –p12 –s courier –C –N3 /etc/motd

piobe is passed the following arguments:

• argc = 10

• argv[0] = /usr/lib/lpd/piobe

• argv[1] – –f

• argv[2] = p

• argv[3] = –z

• argv[4] = 1

• argv[5] = –p

• argv[6] = 12

• argv[7] = –s

• argv[8] = courier

• argv[9] = /etc/motd