Escaping for XML output

       IDENTIFICATION DIVISION.
       PROGRAM-ID. escape-xml.

       DATA DIVISION.
       WORKING-STORAGE SECTION.
       01 ws-e-amp  PIC X(5) VALUE '&'.
       01 ws-e-lt   PIC X(4) VALUE '<'.
       01 ws-e-quot PIC X(6) VALUE '"'.

       01 ws-in  PIC X(100) VALUE 'This <is> a &"string"!'.
       01 ws-out PIC X(600).

       01 ws-n     PIC 9(3) BINARY.
       01 ws-in-i  PIC 9(3) BINARY.
       01 ws-out-i PIC 9(3) BINARY.

       PROCEDURE DIVISION.
           PERFORM VARYING ws-in-i FROM 1 BY 1
               UNTIL ws-in-i > LENGTH OF ws-in
               EVALUATE ws-in(ws-in-i:1)
               WHEN '&' MOVE LENGTH OF ws-e-amp TO ws-n
                        MOVE ws-e-amp TO ws-out(ws-out-i:ws-n)
               WHEN '<' MOVE LENGTH OF ws-e-lt TO ws-n
                        MOVE ws-e-lt TO ws-out(ws-out-i:ws-n)
               WHEN '"' MOVE LENGTH OF ws-e-quot TO ws-n
                        MOVE ws-e-quot TO ws-out(ws-out-i:ws-n)
               WHEN OTHER MOVE 1 TO ws-n
                          MOVE ws-in(ws-in-i:1) TO ws-out(ws-out-i:1)
               END-EVALUATE
               ADD ws-n TO ws-out-i
           END-PERFORM
           DISPLAY ws-in
           DISPLAY ws-out
           STOP RUN
           .