Class: IO
Description
This method reads a record from the device defined by the fileName and directory IO class properties. To use this method, the openParams property must contain READ.
If the charsetName property contains a non-empty value, then characters would have been converted from IO.charsetName to Runtime.charsetName.
Syntax
set PRIM = objectName.read(errorType)
Parameters
|
errorType |
A number identifying an error plus an error description. For example: 0 — No error 1 — End of file 2 — Device device not open This parameter is optional. The default ErrorType is the variable ETYP. As of Profile v7.0, this parameter is deprecated. Use catch blocks to deal with all IO-related exceptions. |
Returns
The value read.
Throws
|
Error |
Cause |
|
%PSL-E-IONOTOPEN |
IO.open has not been called before (i.e., the device has not been opened). |
|
%PSL-E-IOEOF |
Reached the end of file. |
|
%PSL-E-IOOTHER |
Other exception. The Error.description and Error.context may contain additional information. |
When Became Available
v6.4
Example
type IO io = Class.new(“IO”)
set io.directory = ”/unix_directory/spool”
set io.fileName = ”READTEST.txt”
set io.openParams = ”READ”
catch iox {
// if device has been opened, close it
if io.device'="" do io.close()
// if not an IO exception, it's not for us
if iox'["%PSL-E-IO" throw iox
// handle the IO exceptions
if iox["IOOPEN" write "Open failed", ! quit
if iox["IOEOF" write "Reached end of file", ! quit
write "unexpected IO error '", iox.type, "'", !
}
do io.open()
type String PART1,PART2,REC
for set REC = io.read() do {
set PART1 = REC.piece(“,”,1)
set PART2 = REC.piece(“,”,2)
}
*The value of the device property must be a valid file that can be accessed by the user.