Multipart uploading spec

Upload File: abc.txt
Content:
abc
(without typing Enter, just only 'abc', but gedit might append a line feed to the end of the file.)

receive:
undefined-----------------------------17582750441148265109875267035\r\nContent-Disposition: form-data; name="kfm_file"; filename="abc.txt"\r\nContent-Type: text/plain\r\n\r\nabc\n\r\n-----------------------------17582750441148265109875267035\r\nContent-Disposition: form-data; name="MAX_FILE_SIZE"\r\n\r\n9999999999\r\n-----------------------------17582750441148265109875267035\r\nContent-Disposition: form-data; name="upload"\r\n\r\nUpload\r\n-----------------------------17582750441148265109875267035\r\nContent-Disposition: form-data; name="upload_cwd"\r\n\r\n/\r\n-----------------------------17582750441148265109875267035--\r\n

At the beginning, "undefined" is two spaces, since this content was cut from whole request string.