例 5-4　仮想アドレス空間の定義された領域へのセクションのマッピング

     #include <ssdef.h>
     #include <stdio.h>
     #include <stsdef.h>
     #include <descrip.h>
     #include <dvidef.h>
     #include <rms.h>
     #include <secdef.h>

     struct FAB fab;

     char *filename = "maptest.dat";

     char _align(page) buffer[512];

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

          int    status = 0;
          long   flags = 0;
          long   inadr[2];
          long   retadr[2];
          int    fileChannel;

     /********  create disk file to be mapped *************/

          fab = cc$rms_fab;
          fab.fab$l_fna = filename;
          fab.fab$b_fns = strlen( filename );
          fab.fab$l_fop = FAB$M_CIF | FAB$M_UFO;  /* must be UFO */

          status = sys$create( &fab );

          if( status & STS$M_SUCCESS )
             printf("Opened mapfile %s\n",filename);
          else
          {
             printf("Cannot open mapfile %s\n",filename);
             exit( status );
          }
          fileChannel = fab.fab$l_stv;

     /**********  create and map the section  ****************/

          inadr[0] = &buffer[0];
          inadr[1] = &buffer[511];

          printf("inadr[0]=%u,inadr[1]=%u\n",inadr[0],inadr[1]);

          status = SYS$CRMPSC(inadr, /* inadr=address target for map */
                             &retadr, /* retadr= what was actually mapped */
                                   0, /* acmode  */
                                   0, /* flags */
                                   0, /* gsdnam, only for global sections */
                                   0, /* ident, only for global sections */
                                   0, /* relpag, only for global sections */
                         fileChannel, /* returned by SYS$CREATE */
                                   0, /* pagcnt = size of sect. file used */
                                   0, /* vbn = first block of file used */
                                   0, /* prot = default okay */
                                   0 ); /* page fault cluster size */

          if( status & STS$M_SUCCESS )
          {
               printf("Map succeeded\n");
               printf("retadr[0]=%u,retadr[1]=%u\n",retadr[0],retadr[1]);
          }
          else
          {
               printf("Map failed\n");
               exit( status );
          }
     }