This example gets the collating sequence table for the current country and code page.

 #define INCL_DOSNLS     /* National Language Support values */
 #define INCL_DOSERRORS  /* DOS error values                */
 #include <os2.h>
 #include <stdio.h>

 int main(VOID) {
 COUNTRYCODE UserInfo       = {0};       /* Country and code page requested */
 UCHAR       achColSeq[256] = {0};       /* Collating sequence              */
 ULONG       ulSeqLen       = 0;         /* Length of sequence returned     */
 ULONG       i              = 0,         /* Two loop indices                */
             j              = 0;
 APIRET      rc             = NO_ERROR;  /* Return code                     */

    UserInfo.country = 0;      /* Request information about current country */
    UserInfo.codepage = 0;     /* ... and current code page                 */

    rc = DosQueryCollate(sizeof(achColSeq),   /* Length of output area      */
                         &UserInfo,           /* Country and codepage info  */
                         achColSeq,           /* Area for collating sequence*/
                         &ulSeqLen);          /* Length of data returned    */

    if (rc != NO_ERROR) {
        printf("DosQueryCollate error: return code = %u\n",rc);
        return 1;
    }
         /* Show the order of the first 128 characters in the sequence */

   if (ulSeqLen >= 8*16) {
     for (i = 0; i < 8; i++) {
       for (j = 0; j < 16; j++) {
          printf("%3u ", achColSeq[i*16+j]);
          } /* endfor (j) */
       printf("\n");
       } /* endfor (i) */
   } else {
      printf("Unable to show first 128 characters... only %u were returned.\n",
              ulSeqLen);
      return 1;
   }  /* endif */

   return NO_ERROR;
}