Как рассчитать длину контента, например:
POST /Upload/ HTTP/1.1
Host: test.lan
User-Agent: Shockwave Flash
Connection: Keep-Alive
Cache-Control: no-cache
Accept: text/*
Content-Length: ?????
Content-Type: multipart/form-data; boundary=----------------------------4d2179e6b3c0
------------------------------4d2179e6b3c0
Content-Disposition: form-data; name="Filename"
phpinfo.php
------------------------------4d2179e6b3c0
Content-Disposition: form-data; name="ASPSESSID"
6e223eb1c7561e9c599f03cc04e9444b
------------------------------4d2179e6b3c0
Content-Disposition: form-data; name="Filedata"; filename="phpinfo.php"
Content-Type: application/octet-stream
<? phpinfo(); ?>
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Content-Disposition: form-data; name="Upload"
Submit Query
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