#define TAG printf( "# %s(%d)\n", __FILE__, __LINE__ )

##</code><code>##

SV *mapAt( SV *fileMap, U32 hiOff, U32 loOff, size_t size ) {
    SV *map = newSVpvn( "", 0 );
    void *mapAddr;
    size_t n;
TAG;
    printf( "received size: %I64d\n", size );
    ERR( mapAddr = MapViewOfFile(
        (HANDLE)SvUV( fileMap ), FILE_MAP_ALL_ACCESS,
        hiOff, loOff, size
    ));
TAG;
    if( ! size ) { // Mapping entire file
        MEMORY_BASIC_INFORMATION mi;

        ERR( VirtualQuery( mapAddr, &mi, sizeof( MEMORY_BASIC_INFORMATION ) ) );
        size = mi.RegionSize;
        printf( "Actual size mapped: %I64u\n", size );
    }

TAG;
    SvPV_set( map, mapAddr );
    SvCUR_set( map, size );
    SvLEN_set( map, size+1 );
TAG;
    return map;
}