Modifying the PROCLIB(xxxxxxxx) initialization statement

There are several ways by which you can change your dynamic PROCLIB definitions. Here are three methods which you might find useful.

Example 1: 

$T PROCLIB(PROC01),DD(1)=...,DD(2)=...  /* change production PROC dynamically without a restart      */

Always keep in mind how error prone such definitions can be. Repeated use of the $T command is acceptable, of course. If your PROCLIB is large, rather than using a single $T command, which might prove impossible because of command length limitations (consoles: 120 characters; card readers: 70 characters).

Example 2: 

1. $ADD PROCLIB(TEMP01),DD(1)=...       /* copy and add PROC, but do not use                         */
2. $T PROCLIB(TEMP01),DD(2)=...         /* change definitions as required, still do not use          */
3. Test and update TEMP01 as required   /* test until correct                                        */
4. $T PROCLIB(TEMP01),NAME=PROC01       /* change NAME= to production name to override current PROC  */

Entering the correct subscripts on the DD statement can be error prone. If you are building up a concatenation, there is an easier way. The next example takes advantage of the fact that JES2 compresses null DDs out of the concatenation. Note that data sets B, C, and D all specify a high DD subscript (99) which JES2 compresses to the next (lowest) available DD subscript. JES2 renumbers them to 2, 3, and 4, respectively. The example uses operator commands, but you can use the same technique when coding initialization statements.

Example 3: 

1. $ADD PROCLIB(TEMP01),DD(1)=DSN=A... /* Create new PROCLIB concatenation or copy an old one       */
2. $T PROCLIB(TEMP01),DD(99)=DSN=B...  /* but always add to DD number 99. Because JES2 compresses   */
3. $T PROCLIB(TEMP01),DD(99)=DSN=C...  /* null DDs, each $T adds to the end of the concatenation    */
4. $T PROCLIB(TEMP01),DD(99)=DSN=D...  /* (assuming less than 99 DDs)                               */
5. $D PROCLIB(TEMP01)
$HASP319 PROCLIB(TEMP01) DD(1)=DSN=A...
$HASP319                 DD(2)=DSN=B...
$HASP319                 DD(3)=DSN=C...
$HASP319                 DD(4)=DSN=D...
6. Test and update TEMP01 as required    /* test until correct                                        */  
7. $T PROCLIB(TEMP01),NAME=PROC01        /* change NAME= to production name to override current PROC  */

See z/OS JES2 Commands for complete $T PROCLIB(xxxxxxxx) syntax and parameter definition.