To Suppress Linefeed, OPEN "lpt1" BINARY or "LPT1: BIN" RANDOM (35244)

SUMMARY

When the LPRINT statement sends CHR$(13) (a carriage return) to the printer, it automatically adds a linefeed, CHR$(10). This automatic linefeed prevents the ability to overtype or underline a previously printed line.

The following methods let you suppress the automatic linefeed, as shown in complete programs further below:

OPEN "LPT1:BIN" FOR RANDOM AS #n WIDTH#n,255
OPEN "lpt1" FOR BINARY #n
[Note that this method requires the "lpt1" device name to have no colon (:).]

These methods should also be used if you want to send control characters to your printer, such as for printer-graphics mode. Otherwise, the programs below can create garbled graphics output [e.g. the extra linefeed is printed after byte values of 13, and ASCII values of 9 (horizontal tab) are converted to 8 spaces].

This information applies to Microsoft QuickBasic Versions 4.00, 4.00b, and 4.50 for MS-DOS, to Microsoft Basic Compiler Versions 6.00 and 6.00b for MS-DOS and MS OS/2, and to Microsoft Basic PDS Version 7.00 for MS-DOS and MS OS/2.

MORE INFORMATION

You cannot suppress the LPRINT statement's linefeed that is automatically sent along with a carriage return. Instead, you must use PRINT#n to send output to special device names as shown in the examples below.

The following programs demonstrate how to print a carriage return (the ASCII character 13) without an automatic linefeed.

Example of Using "LPT1:BIN" Device Name FOR RANDOM Output

OPEN "LPT1:BIN" FOR RANDOM AS #1
WIDTH#1,255
PRINT #1, "This is a test to do underlining.";
PRINT #1, CHR$(13);
PRINT #1, "_________________________________";
PRINT #1, CHR$(13);
CLOSE #1

Example of Using "LPT1" Device Name FOR BINARY Output

REM  This sample program overprints on one line,
REM  allowing you to underline the text "Seattle Times".
C$ = CHR$(13)         ' 13 = ASCII code for carriage return
LPRINT
OPEN "lpt1" FOR BINARY AS #1
LPRINT "Seattle Times";
PUT #1, , C$
LPRINT "_______ _____"
CLOSE #1
END

Overprinting Using "LPT1:", "LPT1:BIN", and "LPT1:" in Sequence

' This works in QuickBasic but not in GW-Basic.
' This program should output the following:
' program output: hello world
' "hello" should print over itself twice.
CLS
OPEN "lpt1:" FOR OUTPUT AS #1
PRINT #1, "program output:  "
CLOSE
OPEN "lpt1:bin" FOR OUTPUT AS #1
FOR I = 1 TO 3
 
   PRINT #1, CHR$(&HD);    ' Carriage Return with no Line Feed
   PRINT #1, "hello";
 
NEXT
CLOSE
OPEN "lpt1:" FOR OUTPUT AS #1
PRINT #1, " world."
CLOSE
PRINT "done printing"
END