Example: Calling IBM i programs from IBM PASE for i

Interspersed in the following example code are comments that explain the code. Make sure to read these comments as you enter or review the example.

/* This example uses the IBM i PASE _PGMCALL function to call the IBM i
API QSZRTVPR. The QSZRTVPR API is used to retrieve information about
i5/OS software product loads. Refer to the QSZRTVPR API documentation
for specific information regarding the input and output parameters needed 
to call the API */

#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include "as400_types.h"
#include "as400_protos.h"

int main(int argc, char * argv[])
{

   /* IBM i API's (including QSZRTVPR) typically expect character 
      parameters to be in EBCDIC.  However, character constants in 
      PASE for i programs are typically in ASCII. So, declare some 
      CCSID 37 (EBCDIC) character parameter constants that will be 
      needed to call QSZRTVPR */
   
   /* format[] is input parameter 3 to QSZRTVPR and is 
      initialized to the text 'PRDR0100' in EBCDIC */
   const char format[] = 
      {0xd7, 0xd9, 0xc4, 0xd9, 0xf0, 0xf1, 0xf0, 0xf0};
   
   /* prodinfo[] is input parameter 4 to QSZRTVPR and is
      initialized to the text '*OPSYS *CUR  0033*CODE     ' in EBCDIC 
      
      This value indicates we want to check the code load for Option 33 
      of the currently installed i5/OS release */
   const char prodinfo[] = 
      {0x5c, 0xd6, 0xd7, 0xe2, 0xe8, 0xe2, 0x40, 0x5c, 0xc3,
       0xe4, 0xd9, 0x40, 0x40, 0xf0, 0xf0, 0xf3, 0xf3, 0x5c,
       0xc3, 0xd6, 0xc4, 0xc5, 0x40, 0x40, 0x40, 0x40, 0x40}; 
   
   /* installed will be compared with the "Load State" field of the 
      information returned by QSZRTVPR and is initialized to the text 
      '90' in EBCDIC */
   const char installed[] = {0xf9, 0xf0};

   /* rcvr is the output parameter 1 from QSZRTVPR */
   char rcvr[108];
   
   /* rcvrlen is input parameter 2 to QSZRTVPR */
   int rcvrlen = sizeof(rcvr);
   
   /* errcode is input parameter 5 to QSZRTVPR */
   struct {
      int bytes_provided;
      int bytes_available;
      char msgid[7];
   } errcode;

   
   /* qszrtvpr_pointer will contain the IBM i 16-byte tagged 
      system pointer to QSZRTVPR */
   ILEpointer qszrtvpr_pointer;
   
   /* qszrtvpr_argv6 is the array of argument pointers to QSZRTVPR */
   void *qszrtvpr_argv[6];

   /* return code from _RSLOBJ2 and _PGMCALL functions */
   int rc;
   
   /* Set the IBM i pointer to the QSYS/QSZRTVPR *PGM object */
   rc = _RSLOBJ2(&qszrtvpr_pointer,
                 RSLOBJ_TS_PGM,
                 "QSZRTVPR",
                 "QSYS");

   /* initialize the QSZRTVPR returned info structure */
   memset(rcvr, 0, sizeof(rcvr));

   /* initialize the QSZRTVPR error code structure */
   memset(&errcode, 0, sizeof(errcode));
   errcode.bytes_provided = sizeof(errcode);

   /* initialize the array of argument pointers for the QSZRTVPR API */
   qszrtvpr_argv[0] = &rcvr;
   qszrtvpr_argv[1] = &rcvrlen;
   qszrtvpr_argv[2] = &format;
   qszrtvpr_argv[3] = &prodinfo;
   qszrtvpr_argv[4] = &errcode;
   qszrtvpr_argv[5] = NULL;

   /* Call the IBM i QSZRTVPR API from PASE for i */
   rc = _PGMCALL(&qszrtvpr_pointer, 
                 (void*)&qszrtvpr_argv, 
                 0);

   /* Check the contents of bytes 63-64 of the returned information.
      If they are not '90' (in EBCDIC), the code load is NOT correctly 
      installed */
   if (memcmp(&rcvr[63], &installed, 2) != 0)
      printf("IBM i Option 33 is NOT installed\n");
   else
      printf("IBM i Option 33 IS installed\n");

   return(0);
}