send_file pdf problem

For me it works fine for code:

file_path=c:/pdfs/file.pdf
send_file(file_path,
              :filename => File.basename(file_path),
              :type => 'application/pdf',
              :disposition => 'inline',
              :streaming => 'true',
              :buffer_size => 4096) <-- I changed that.

But in fact I'm still in development stage and I haven't tried it on
Apache server.