Read STDIN (SYSIN) in COBOL

I want to read the lines out of STDIN (aka SYSIN) in COBOL. For now I just want to print them out so that I know I've got them. From everything I'm reading it looks like this should work:

IDENTIFICATION DIVISION.
PROGRAM-ID. APP.

ENVIRONMENT DIVISION.
INPUT-OUTPUT SECTION.
FILE-CONTROL.

    SELECT SYSIN ASSIGN TO DA-S-SYSIN ORGANIZATION LINE SEQUENTIAL.

DATA DIVISION.
FILE SECTION.

FD SYSIN.
01 ln PIC X(255).
    88 EOF VALUE HIGH-VALUES.
WORKING-STORAGE SECTION.

PROCEDURE DIVISION.
    OPEN INPUT SYSIN
    READ SYSIN
      AT END SET EOF TO TRUE
    END-READ
    PERFORM UNTIL EOF
        DISPLAY ln
        READ SYSIN
            AT END SET EOF TO TRUE
        END-READ
    END-PERFORM
    CLOSE SYSIN
    STOP RUN.

That compiles (using open-cobol and cobc -x), but running it I get:

libcob: File does not exist (STATUS = 35) File : ''

What am I doing wrong?

Solution

The following was suggested to me on the OpenCOBOL forums.

SELECT SYSIN ASSIGN TO KEYBOARD ORGANIZATION LINE SEQUENTIAL.

It's the keyword KEYBOARD that makes it work.

Apparently DISPLAY is a similar word for STDOUT, but I have not tested that.