Duplicate input files

Hardware/OS: IBM MVS
Cobol : Cobol II (Cobol 85 standard)


Down the pub last night a former colleague told me of a problem using
the same file via two DDs as input to a batch Cobol program. Under MVS
he gave each DD a disp=shr but received an error message preventing
successful execution. (Unfortunately, he's gone shopping so the exact
message is unspecified here). He resolved the problem by duplication of
the file so there would be no disp conflicts. Neither he nor I know of
any reason why duplicate DDs with disp=shr would fail. Has anyone got
any answer?

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