Spooler Programmer's Guide

Spooler Procedure Calls
Spooler Programmer’s Guide—522287-002
4-10
Considerations
returns a line of spooled data.
read-count input
INT:value
specifies the maximum number of bytes to be read.
count-read output
INT:ref:1
is the number of bytes actually read.
pagenum input
INT:value
returns one of the following:
Considerations
The following considerations apply to the use of the PRINTREAD procedure:

The size of data-line never exceeds 450 words; however, in most cases, it is
smaller.

Errors returned from PRINTREAD other than %12000-%12001 and %12003-
%12005 are critical. In the case of a print process (not for perusal processes), the
error should be sent to the supervisor using PRINTSTATUS.

When the error-code returns %12003 = CONTROL found, the data line contains
a file-system CONTROL message for the print device. The format of the
CONTROL message is
data-line [0] = operation
data-line [1] = parameter
See the Guardian Procedure Calls Reference Manual for a description of the
CONTROL operations.

When the error-code returns %12004 = SETMODE found, the data line contains
a file-system SETMODE instruction. The SETMODE instruction format is
data-line [0] = SETMODE function
data-line [1] = param-1
data-line [2] = param-2
> 0 PRINTREAD returns the first line on the page specified by this
parameter.
< 0 PRINTREAD repeats the last line returned.
= 0 or
absent
PRINTREAD returns the next sequential line.