In the following example, a data set is deleted and then reallocated, and two JCL symbols–DSNAME and VOLSER–are exported and used for symbol substitution in the in-stream data sets:

//REALLOC  JOB 1,TESTJOB,    
//          MSGLEVEL=(1,1),CLASS=A
//E1  EXPORT SYMLIST=(DSNAME) 
//E2  EXPORT SYMLIST=(VOLSER)     
//S1  SET    DSNAME=HASP.TEST.MACLIB
//S2  SET    VOLSER=J2COM1
//DEALLIB EXEC PGM=IDCAMS,REGION=300K 
//DD1       DD UNIT=3390,DISP=OLD,VOL=SER=&VOLSER
//SYSPRINT  DD SYSOUT=* 
//SYSIN     DD *,SYMBOLS=JCLONLY 
            DELETE  &DSNAME  
            NONVSAM PURGE SCRATCH FILE(DEVICE)
//*               
//REALLIB EXEC PGM=IKJEFT01,REGION=300K  
//SYSTSPRT  DD SYSOUT=*        
//SYSTSIN   DD *,SYMBOLS=JCLONLY 
            ALLOCATE DSNAME('&DSNAME.') 
            UNIT(3390) VOLUME(&VOLSER.) 
            NEW CATALOG DSNTYPE(LIBRARY)
            SPACE(65,15)  DIR(56)   TRACKS