START KEY EQUAL TO

I am working with a client who is using a START ...KEY IS EQUAL TO. We
are migrating the code from an MVS system to Windows. The FD for the
file is similar to:

FD Filename
01 KEY-REC.
05 PRIME-KEY.
10 PK-VAR1 PIC 99.
10 PK-VAR2 PIC X(10).
10 PK-VAR3 PIC X(3).
10 PK-VAR4 PIC X(2).
10 PK-VAR5.
15 PK-VAR5A PIC X(2).
15 PK-VAR5B PIC X(4).
15 FILLER PIC X(10).
10 PK-VAR6 PIC 9(4).
05 PK-KEY1 REDEFINES PRIME-KEY PIC X(17).

They supply values for PK-KEY1 and do a START on it (START filename KEY
IS EQUAL TO PF-KEY1). They say this works on the mainframe. In the PC
environment we are receiving an error (file status '23': Record not
found). We agree with the PC version and have asked for a mainframe
output to show this working.

The logic being this is a partial key. When an EQUAL TO is used
'partial keys' can not be used. Is this correct? Can partial keys be
used when a START EQUAL TO is?

Thank you for all your insight and assistance!

Long Live COBOL!!!

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