Use EDGXMP2 to display volume information, as shown in this example:

/*REXX*****************************************************************/
/*                                                                    */
/* DSNLIST EXEC -  Given any volume serial number it displays all the */
/*                 information held by DFSMSrmm about the data sets on*/
/*                 the volume.                                        */
/*                                                                    */
/* Variables used from SEARCHDATASET command:                         */
/*            edg@dsn.0 - number of data sets on the volume.          */
/*            edg@dsn.x - data set name of each of the data sets on   */
/*                        volume (x=1 to edg@dsn.0).                  */
/*            edg@vol.x - volume serial number (x=1 to edg@dsn.0)     */
/*            edg@seq.x - data set sequence number (x=1 to edg@dsn.0) */
/*                                                                    */
/**********************************************************************/
arg volser                          /* Use parameter supplied as the  */
                                    /* volume serial.                 */

Do while volser = ''                /* No volume serial so ask for one*/
  Say "Enter Volume Serial:"        /* Issue prompt to TSO user       */
  Pull volser                       /* Get volume serial from TSO user*/
end

sysauth.edgdate = "EUROPEAN"        /* Tell RMM TSO command to return */
                                    /* output as REXX variables and   */
                                    /* dates in EUROPEAN (DD/MM/YYYY) */
                                    /* format.                        */
save_prompt = prompt("OFF")         /* Turn PROMPTing off.            */
save_msg    = msg("OFF")            /* Turn messages off.             */
                                    /* Get information for data sets  */
                                    /* on the volume                  */
address "TSO" "RMM SEARCHDATASET D(*) VOLUME("volser") LIMIT(*)"
junk = msg(save_msg)                /* Restore previous message status*/

If rc = 0 then
  do
    drop sysauth.edgdate            /* Tell the RMM TSO command to    */
                                    /* return output via messages.    */

                                    /* Display data set listed by the */
                                    /* Search command until all are   */
                                    /* displayed or non-zero return   */
                                    /* code received.                 */
   Do dataset = 1 to edg@dsn.0 while (rc = 0)
      address "TSO" "RMM LISTDATASET '"edg@dsn.dataset"'
                     VOLUME("edg@vol.dataset") SEQ("edg@seq.dataset")"
      say ""                        /* Write a couple of extra blank  */
      say ""                        /* lines                          */
    end
                                    /* complete with a summary        */
    say edg@dsn.0 "Data sets on volume "volser" displayed."
  end
else
  do
    drop sysauth.edgdate            /* An error has occurred.  Tell   */
                                    /* the RMM TSO command to return  */
                                    /* output via messages.           */
                                    /* Get error information from     */
                                    /* DFSMSrmm.                      */
    say "SEARCHDATASET D(*) VOLUME("volser") LIMIT(*)"
    address "TSO" "RMM SEARCHDATASET D(*) VOLUME("volser") LIMIT(*)"
  end
junk = prompt(save_prompt)          /* Restore PROMPT status.         */
exit(0)                             /* return to caller               */