function  [count, errmsg]= nano3write(filename, header, img)
%NANO3WRITE  Write the header and the image to a nanoscope file.
%
%       [COUNT, ERRMSG] = NANO3WRITE(FILENAME, HEADER, IMAGE)
%
%       Return the number of elements successfully written.
%              and an error message if occour.
%
%       Before to write the file, the image is -90 degree
%       rotated to be compatible with the nanoscope.
%
%
%       Claudio  October 2, 1994.

%
% Copyright (c) 1995 by Claudio Rivetti and Mark Young
% claudio@alice.uoregon.edu,    mark@alice.uoregon.edu
%


fp = fopen(filename, 'w');

if fp == -1
    errmsg='Can not create file';
    return;
end


img=rot90(img, -1);
count_header = fwrite(fp, header', 'char');
count_img    = fwrite(fp, img, 'short', 'vaxd');
em=ferror(fp, 'clear');
fclose(fp);

count = prod(size(header)) + prod(size(img));

if count ~= count_header + count_img
    errmsg=em;
end

return