If you do not plan to define an IEFJOBS concatenation in MSTJCLxx and the procedure DUMPCHK is already defined in SYS1.PROCLIB or one of the other data sets in the IEFPDSI concatenation of MSTJCLxx, use a JOB statement in the DUMPCHK member that formerly contained only the procedure, along with an EXEC statement that will run the existing procedure, and convert the existing procedure to an in-stream procedure by adding PROC and PEND statements, if they are not already present. For example:

//DUMPCHK  JOB  'accounting_info',MSGLEVEL=(1,1)
//DUMPCHK  PROC
//DUMPCHK  EXEC PGM=DMPCHKO,REGION=5M,PARM='/&SG,&JDATE,&DAY'
//STEPLIB  DD   DSN=JCR.PGM.LOAD,DISP=SHR
//CDS      DD   DSN=DATAMGT.CDS,DISP=SHR
//         DD   DSN=DATAMGT.CDS.CLEAR,DISP=SHR
//         DD   DSN=DATAMGT.CDS.Y43DUMPS,DISP=SHR
//LOG      DD   DSN=SYS1.TSODUMP.LOG,DISP=SHR
//SYSPRINT DD   SYSOUT=*
//         PEND
//         EXEC DUMPCHK

When the START command is issued, MVS™ inserts a JCL SET statement after the JOB statement, resulting in the following JCL:

//DUMPCHK  JOB  'accounting_info',MSGLEVEL=(1,1)
//         SET  SG=ALL,JDATE=93119,DAY=THURSDAY
//DUMPCHK  PROC
//DUMPCHK  EXEC PGM=DMPCHKO,REGION=5M,PARM='/&SG,&JDATE,&DAY'
//STEPLIB  DD   DSN=JCR.PGM.LOAD,DISP=SHR
//CDS      DD   DSN=DATAMGT.CDS,DISP=SHR
//         DD   DSN=DATAMGT.CDS.CLEAR,DISP=SHR
//         DD   DSN=DATAMGT.CDS.Y43DUMPS,DISP=SHR
//LOG      DD   DSN=SYS1.TSODUMP.LOG,DISP=SHR
//SYSPRINT DD   SYSOUT=*
//         PEND
//         EXEC DUMPCHK