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move the number 129 into the AX thingy, then
make the value ax ax into some weird thing, then
just clear the screen because I feel like it.

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moving memory:
To move memory, copy source memory to target memory. Increment both of those, and repeat until executed as many times as needed.
....
to refresh the screen:
move the memory from video buffer to address 0xb8000 80*25*2 times.

Code: Select all

int main()
{
    // This will be used to iterate through "from" files vector
    char const * const * p;
    // Handle for handling memory used by function
    struct RDArgs *rda;
    // One array element per template element
    LONG vec[3] = {};
    // Third parameter to ReadArgs() can be a struct RDArgs 
    // holding e.g. additional help text to be displayed on 'copy ?'
    if ( ( rda = ReadArgs( "From/M,To/A,All/S", vec, NULL ) ) != NULL )
    {
        // 'From/M' - 'From' is the keyword, '/M' means "multi",
        // i.e. return type is an array of char pointers.
        // Because 'From/M' was the first element in the template,
        // the pointer to that array is the first element in the return vector.
        // Array of char pointers ends with a NULL element.
        if ( ( p = ( char const * const *)vec[0] ) != NULL )
        {
            for ( ; *p != NULL; ++p )
            {
                printf( "File  = %s\n", *p );
            }
        }
        // 'To/A' - 'To' is the keyword, '/A' means it is compulsory
        // to provide this option. No multi, so return type is a pointer
        // to a C string. Second template entry, second array element.
        printf( "To    = %s\n", (char const *)vec[1] );
        // 'All/S' - 'All' is the keyword, '/S' means it is a switch.
        // Return type is a boolean.
        printf( "All   = %s\n", vec[2] ? "TRUE" : "FALSE" );
        // ReadArgs() had to store the parsed tokens somewhere, so
        // we have to release them.
        FreeArgs( rda );
    }
    else
    {
        printf( "Error while parsing options.\n" );
    }
    return 0;
}