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Read records sequentially from a subfile

Can we use READ opcode to read records from a subfile record format(Data part)?

Yes, you can read records sequentially from a subfile, but you would do it using the CHAIN operation because a subfile is a 'direct' file. That means that a subfile is accessed using its relative record numbers.

So to read the subfile, use the subfile record number field you defined on the F-spec for the display file in a DO or FOR loop, starting at value 1 and ending at the last record number in the subfile -- you should know that value through having loaded the subfile in the first place.

You code would look like this :

 C                   For       ##SFR3 = 1 to LastRec 
C     ##SFR3        Chain (E) #SFL3         
C                   Update    #SFL3 
C                   EndFor         

Between the Chain and the Update you can do what you like!

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