IBM AS/400 manual Accessing, Types of Device Files Chapter, Attached, 315

Types of Device Files

Chapter

17.

Accessing

Externally

Attached

Devices

You can access externally attached

devices

from

RPG

by

using

devic

Device

files

are files that provide access to externally attached har

printers, tape units, diskette units, display stations, and other syst

attached

by

a

communications

line.

This chapter describes how to access externally attached devices

device names

PRINTER,

SEQ,

and

SPECIAL.

For

information

on

display stations

and

ICF devices see Chapter 18, “Using

WORKSTN

Files” on page 331

Types

of Device

Files

Before your program can read or write to the devices on the syst

description

that

identifies

the

hardware

capabilities

of

the

devic

system

must

be

created

when

the

device

is

configured.

A device

f

a

device

can

be

used.

By referring to a specific

device

file,

the device in the way

that it is described to the system. The

output data from your RPG

program

for

presentation

to

the

device,

a

input

data

from

the

device

for

presentation

to

your

RPG

program.

You use the device files listed in Table 22 to

access

the

associa

attached

devices:

Table

22.

AS/400 Device Files, Related CL commands, and RPG Device Name

Device

Associated

Externally

Attached

Device

CL com-

RPG

File

mands

Device

Name

Printer

Provide

access

to

printer

devicesCRTPRTFand

PRINTER

Files

describe

the

format

of

printed

CHGPRTFoutput.

OVRPRTF

Tape

Files

Provide

access

to

data

files

whichCRTTAPF are

SEQ

stored

on

tape

devices.

CHGTAPF

OVRTAPF

Diskette

Provide

access

to data files whichCRTDKTFare

DISK

Files

stored

on

diskette

devices.

CHGDKTF

OVRDKTF

Display

Provide

access

to

display

devicesCRTDSPF.

WORKSTN

Files

CHGDSPF

OVRDSPF

ICF

Files

Allow

a

program

on one system to comCRTICFF-

WORKSTN

municate

with

a

program

on

the

sameCHGICFF

system

or

another

system.

OVRICFF

The

device

file

contains

the

file

description,

which

identifies the

it

does

not

contain

data.

 Copyright IBM Corp. 1994, 1999 315