COBOL data buffering without moving character by character

Question

I am reading a variable length input file and wanting to create an output buffer (indexed table) that will not utilize a character by character move.

For example: my first input record is 79 characters, I can then move this to my group level of the table. My second input record is 101 characters -- how can I take these 101 characters and place them in my table beginning at position 80 for a length of 101 ? And the next input record beginning at position 180.....etc. We currently Perform Varying 1 by 1 but this is incredibly CPU intensive compared to a block move to a beginning address.

We do this millions of times a day and a solution would be quite useful.

Answer 1

Use reference modification with the length from your record. Consider:

01 Record
  05 Rec-LL  Pic S9(4) Binary.
  05 Rec-Data Pic X(32767).
01 Tgt-Area Pic X(10000000).
01 Curr-Ptr   Pic S9(8) Binary.

Once you read your record, you can move based on the length like so:

   Move 1 to Curr-Ptr
   Perform Get-Next-Record
   Perform until no-more-data
      Move Rec-Data (1:Rec-LL) to Tgt-Area (curr-ptr:rec-LL)
      Compute Curr-Ptr = Curr-Ptr + Rec-LL
      Perform Get-Next-Record
   End-Perform

Answer 2

Or the old fashioned ( we are talking COBOL here so old fashioned = Jurassic) way:-

    01 Record.
       05 REC-LL           PIC S9(4) Binary.
       05 REC-DATA.
          10  REC-BYTES PIC X OCCURS 32767 times depending on REC-LL.

    01 TARGET-AREA.
       05 TARGET-HEADER       PIC X(79).
       05 TARGET-REC          PIC X(101) OCCURS 50 TIMES.

    01 TGT-INDEX              PIC S9(8) BINARY VALUE 1.

   *  Length calculation happens by magic!

       Perform Read-Record.
       move REC-DATA TO TARGET-HEADER.
       perform until no-more-data 
           Perform Read-Record
           move REC-DATA to TARGET-RED(TGT-INDEX)
           add +1 to TGT-INDEX
       end-perform

Or if records really vary between 1 and 101 bytes:

    01 Record.
       05 REC-LL           PIC S9(4) Binary.
       05 REC-DATA.
          10  REC-BYTES PIC X OCCURS 32767 times depending on REC-LL.

    01 TARGET-AREA.
       05 TGT-LL              PIC s9(8) BINARY.
       05 TGT-REC.
          10  TGX-BYTE        OCCURS 3175 depending on TGT-LL.
       05 TGT-EXTRA           PIC X(101). 




       Perform Read-Record.
       Move +0 to tgt-LL.
       perform until no-more-data
           MOVE REC-DATE to TGT-EXTRA
           ADD REC-LL TO TGT-LL
           Perform Read-Record
           add +1 to TGT-INDEX
       end-perform

Answer 3

Take a look at the STRING INTO verb, in particular the WITH POINTER clause. Don't forget the ON OVERFLOW imperative when stringing things together like this.

For details, grab a copy of Gary Cutler's OpenCOBOL Programmer's Guide.

http://opencobol.add1tocobol.com/OpenCOBOL%20Programmers%20Guide.pdf

This is a world class COBOL manual, and it's an open and free document (GNU FDL).