Hello,

We are trying to define a 64bit area for a pointer (in case we decide to move to AMODE 64).

We tried to use the __ptr64 qualifier, but it was rejected because (as it turns out) this is only supported in Metal C.

Is there an equivalent for a non Metal ILP31 program?

We looked in  'SYS1.SIEAHDR.H(IHACHDR)' and see this...

#ifndef __ptr64_t                       
#define __ptr64_t                       
  #if defined(__IBM_METAL__)            
    typedef void * __ptr64 ptr64_t;     
  #elif defined(_LP64)                  
    typedef void * ptr64_t;             
  #else                                 
    typedef unsigned long long ptr64_t; 
  #endif                                
#endif        

Is there a way we can create a qualifier that acts similarly to __ptr64?  

So, we could use something like char * __ptr64likequaliefier myStuffPtr;  ?

My understanding is that we would need the qualifier to indicate the length but the pointer type to indicate the type of pointer. 

Thank you!

Nancy

hi Nancy,

Unfortunately there is no way to add in a qualifier via typedef or other language mechanism as those are syntax constructs. The best approach is what was shown in the header: Using an "unsigned long long" type and casting it as needed.

Hope this helps.

Back in my PL/X days, I think we did something like this:

dcl
   1 abigstructure,
      3 <some stuff>      
      3 a64bitpointer ptr(64),
         5 * fixed(32),
         5 a31bitpointer ptr(31),
     3 <more stuff>
   ;

So we could reserve the space for the high order word of a future 64-bt pointer for future use.

I think you could probably come up with an analogous "struct" in C the does something similar?

In the future you'd need to do a "change all" in the functional code from a31bitpointer to a64bitpointer or use better names and just change the variable name in the structure...

<apologies to those reading, Nancy and I have a history of torturing each other over which language is better...>

Scott

Good Analysis. Scott Fagen

dcl   1 abigstructure,      3 <some stuff>            3 a64bitpointer ptr(64),         5 * fixed(32),         5 a31bitpointer ptr(31),     3 <more stuff>   ;