/*
/*
 *                          COPYRIGHT (C) 1998, 2000 BY
 *                      COMPAQ COMPUTER CORPORATION, HOUSTON
 *                         TEXAS.  ALL RIGHTS RESERVED.
 *
 *    THIS SOFTWARE IS FURNISHED UNDER A LICENSE AND MAY BE USED AND COPIED
 *    ONLY IN ACCORDANCE WITH THE TERMS OF SUCH LICENSE AND WITH THE INCLUSION
 *    OF THE ABOVE COPYRIGHT NOTICE.  THIS SOFTWARE OR ANY OTHER COPIES
 *    THEREOF MAY NOT BE PROVIDED OR OTHERWISE MADE AVAILABLE TO ANY OTHER
 *    PERSON.  NO TITLE TO AND OWNERSHIP OF THE SOFTWARE IS HEREBY TRANSFERRED.
 *
 *    THE INFORMATION IN THIS SOFTWARE IS SUBJECT TO CHANGE WITHOUT NOTICE AND
 *    SHOULD NOT BE CONSTRUED AS A COMMITMENT BY COMPAQ COMPUTER CORPORATION.
 *
 *    COMPAQ ASSUMES NO RESPONSIBILITY FOR THE USE OR RELIABILITY OF ITS
 *    SOFTWARE ON EQUIPMENT THAT IS NOT SUPPLIED BY COMPAQ.
 *
 *    NO RESPONSIBILITY IS ASSUMED FOR THE USE OR RELIABILITY OF SOFTWARE
 *    ON EQUIPMENT THAT IS NOT SUPPLIED BY COMPAQ COMPUTER CORPORATION.
 *
 *    SUPPORT FOR THIS SOFTWARE IS NOT COVERED UNDER ANY COMPAQ SOFTWARE
 *    PRODUCT SUPPORT CONTRACT, BUT MAY BE PROVIDED UNDER THE TERMS OF THE
 *    CONSULTING AGREEMENT UNDER WHICH THIS SOFTWARE WAS DEVELOPED.
 */
/*
    Compilation and link commands:

     $ CC/DEBUG/NOOPT CRMPSC.C
     $ LINK/DEBUG CRMPSC,SYS$INPUT/OPT
       PSECT_ATTR=G_SNS_COMMON,PIC,NOEXE,SHR

*/

#include <string.h>
#include <stdlib.h>
#include <starlet.h>         /* For the usage of sys$crmpsc */
#include <descrip.h>         /* Because we need the macro $DESCRIPTOR */
#include <secdef.h>          /* For the SEC$M_ flags */
#include <stsdef.h>          /* For the $VMS_STATUS_SUCCESS macro */
#include <rms.h>
#include <lib$routines.h>
#include <psldef.h>
#include <syidef.h>

#define PAGELET_SIZE 512     /* CRMPSC, for the flags we use, counts in number
                              * of pagelets, so define the size of a pagelet.
                              */
int dummy_array_for_offsets [10];
#pragma extern_model save
#pragma extern_model common_block
struct {
        int starting;
        int ending;
}  g_sns_common;
#pragma extern_model restore

#pragma member_alignment save
#pragma nomember_alignment
typedef struct {
        unsigned short buflen;
        unsigned short item_code;
        void *buffer;
        unsigned int *retadr;
} item_t;
#pragma member_alignment restore

main(){
  unsigned long inadr[2];
  unsigned long retadr[2];
  struct FAB fab;
  item_t *itmlst;
  unsigned int pagesize;
  char *filename = "IARRAY.DAT";
  int pagcount,flags,status;
  $DESCRIPTOR (global_section_name_descriptor,"IARRAY");

  itmlst = calloc(2,sizeof(item_t));
  /*
   * Get the CPU specific page size.
   */
  itmlst[0].buflen = sizeof(unsigned int);
  itmlst[0].item_code = SYI$_PAGE_SIZE;
  itmlst[0].buffer = &pagesize;
  itmlst[0].retadr = NULL;
  status = sys$getsyiw(0,0,0,itmlst,0,0,0);
  if (!$VMS_STATUS_SUCCESS(status)) lib$signal (status);
  /*
   * Compute the starting and ending addresses to the next CPU-specific
   * page boundary,because we are on an Alpha System and we do NOT use
   * SEC$M_EXPREG in the flags argument.
   */
  inadr[0] = (unsigned long)&g_sns_common.starting;
  inadr[1] = (unsigned long)((char *)&g_sns_common.ending +
                sizeof(int)+pagesize)/pagesize*pagesize - 1;
  pagcount = (inadr[1]-inadr[0])/PAGELET_SIZE;
  /*
   * As we are mapping a new page file section, create the file with $ create.
   */
  fab = cc$rms_fab;
  fab.fab$l_alq = pagcount;
  fab.fab$b_fac = FAB$M_GET | FAB$M_PUT;
  fab.fab$l_fna = filename;
  fab.fab$b_fns = strlen(filename);
  fab.fab$l_fop = FAB$M_UFO | FAB$M_CIF;
  status = sys$create(&fab);
  if (!$VMS_STATUS_SUCCESS(status)) lib$stop(status);
  /*
   * Specify the desired flags
   */
  flags =  SEC$M_GBL | SEC$M_WRT | SEC$M_SYSGBL | SEC$M_DZRO;

  /* Now create the global section */
  status = sys$crmpsc ( inadr,
                        retadr,
                        PSL$C_USER /* acmod not specified */,
                        flags,
                        &global_section_name_descriptor,
                        0 /* ident not specified */,
                        0 /* relpag not specified */ ,
                        fab.fab$l_stv /* file channel returned by $create */,
                        pagcount,
                        0 /* vbn not specified */,
                        0 /* prot not specified */,
                        0 /* pfc not specified */);
  /*
     With the debugger check status with an EXAMINE/CONDITION status
     Examine in hexadecimal retadr
     Still with the debugger, type SPAWN and with the VMS prompt, enter
     INSTAL. Under INSTAL type LIST/GLOBAL. Locate the section IARRAY.
     Is the number of pagelets rounded up to next machine page size correct
     for our section ?
   */
   return status;
}