When a Format 5 DISPLAY statement is specified, the value stored in
  envlog-name is moved to environment-name. See ENVIRONMENT-NAME in
  the SPECIAL-NAMES paragraph. The updated value of environment-name
  becomes the environment variable or logical to be accessed by
  subsequent Format 6 DISPLAY and Format 8 ACCEPT statements.

  Format 5 -

   DISPLAY envlog-name UPON environment-name
      [ END-DISPLAY ]

1  –  envlog-name

  references an alphanumeric data item, or is a nonnumeric literal.

2  –  environment-name

  is a mnemonic name associated with ARGUMENT-NUMBER in the
  SPECIAL-NAMES paragraph in the Environment Division, representing
  the name of an environment variable or system logical.

3  –  Example

  Example of Formats 5 and 6.

 IDENTIFICATION DIVISION.
 PROGRAM-ID. SAMPLE.
 ENVIRONMENT DIVISION.
 CONFIGURATION SECTION.
 SPECIAL-NAMES.
   ENVIRONMENT-NAME    IS NAME-OF-EVAR
   ENVIRONMENT-VALUE   IS VALUE-OF-EVAR.
 DATA DIVISION.
 WORKING-STORAGE SECTION.
 01 NAME-1                  PIC X(20).
 01 VALUE-ACCEPTED          PIC X(20).
 PROCEDURE DIVISION.
 P1.
 *       The name of the environment variable
         MOVE "TESTPATH1" TO NAME-1.

 *       Create an environment with the name "TESTPATH1"
         DISPLAY NAME-1 UPON NAME-OF-EVAR.

 *       Set the value of "TESTPATH1"
         DISPLAY "/USER/MYNAME" UPON VALUE-OF-EVAR.

 *       Read the value of TESTPATH1 into a variable
         ACCEPT VALUE-ACCEPTED FROM VALUE-OF-EVAR.

 *       Display the value of TESTPATH1"
         DISPLAY VALUE-ACCEPTED.

         STOP RUN.