Invalid length error while passing parameters to ispf macro from rexx code

Question

I have written a macro to change a string all members of PDS. I am passing PDS, existing value and new value via JCL. I am getting invalid length error while passing arguments to ispf macro using rexx. Error is :

ISPS108 Invalid length    -/-Parameter 'PARM' exceeds the allowable length.

My REXX code - IWPURDX is :

TRACE "ALL"                                                         
ARG PDS STRING1 STRING2 .                                           
MAC  = 'TEMPMAC'                               /* Macro name        
*/                                                                  
PDS = STRIP(PDS,"B","'")                                            
STRING1 = STRIP(STRING1,"B","'")                                    
STRING2 = STRIP(STRING2,"B","'")                                    
S12 = STRING1 || " " || STRING2                                     
SAY "STRING1" STRING1                                               
SAY "STRING2" STRING2                                               
SAY "S12" S12                                                       
SAY "LENGTH" LENGTH("S12")                                          
X = OUTTRAP("LIBMEM.")                         /* Trap output of TSO
*/                                                                  
 ADDRESS TSO "LISTDS '"PDS"' M"                                     
 X = OUTTRAP("OFF")                                           

DO I = 7 TO LIBMEM.0                                         
  LIBMEM.I = STRIP(LIBMEM.I)                   /* Member name
*/                                                           
  ADDRESS ISPEXEC "EDIT DATASET ('"PDS"("LIBMEM.I")') " ||,  
    "MACRO ("MAC") PARM ("S12")"                             
  SAY I RC LIBMEM.I                                          
END

ISPF Macro - TEMPMAC is :

 /*REXX*/                                       
 TRACE "ALL"                                    
SAY "TEMPMAC"                                   
ADDRESS ISREDIT "MACRO (PARM) PROCESS"          
PARSE VAR PARM STRING1 STRING2                  
ADDRESS ISREDIT "CHANGE ALL 'STRING1' 'STRING2'"
C_RC = RC                                       
ADDRESS ISREDIT "END"                           
EXIT C_RC                                       

In JCL, I am calling them via below ISPF command :

//REXX  EXEC PGM=IKJEFT01,REGION=32M                               
//SYSPRINT DD  SYSOUT=*                                            
//SYSTSIN  DD  *                                                   
  ISPSTART CMD(%IWUPDRX 'PPPRG3.BASE.WRJCL' '2016-01-01' 'IWPULDT')
/*                                                                 

I also printed the length so string passed to macro - it says 3. I am not able to get root cause of error. Can somebody please help ?

Answer 1

Think your edit PARM is waiting for a variable name, not the value.

ADDRESS ISPEXEC "EDIT DATASET ('"PDS"("LIBMEM.I")') " ||,  
    "MACRO ("MAC") PARM ("S12")"

So try to replace "... PARM ("S12")" with "... PARM (S12)"

Answer 2

As Fritz and zarchasmpgmr pointed out PARM must point at a variable name. We would need to see the macro and the exec to make sure we know what you mean by hard coding the parameter in TEMPMAC and just passing the macro name. PARM is an optional parameter so it is not required by EDIT. If PARM is specified then the ISPF code will look for a variable name. So the code looks at the storage pointed to by the parameter. Since it is supposed to be a variable name the code is parsing the storage for an 8 byte field that meets the criteria for a NAME. The code will look for what is between the parens. The ISPS108 occurs when what is between the parens is greater than 8 bytes with no delimiter. If what is in storage meets a NAME definition then we continue and later check to see what this variable name contains by calling TSO to supply the variable value. If PARM is not coded then we just bypass the processing as the optional parameter is not present.

Answer 3

Passing parms the way you have done here is a bad idea. It's better to VPUT them to a variable pool inside the calling exec then VGET them inside the macro.

Although in this case the values of STRING1 and STRING2 must be single tokens/words (because that's how they were created by the ARG statement in the exec) the vput/vget approach allows you to pass arbitrary strings into the macro. There's no point in concatenating them into a single variable and then parsing that apart in the macro, just vput & then vget both of them.

Once you have the in a macro your 'isredit change' command won't work in some circumstances, depending on what the values of string1 and string2 actually are. Eg imagine if they contained words like FIRST LAST which are also valid parameters for a change command?

I used to do

hexstring1 = c2x(string1)
hexstring2 = c2x(string2)
"address isredit change x'"hexstring1"' '"hexstring2"' all"

in such macros so that it's completely irrelevant what the contents of the strings are.