LIS 525 - HTTP demonstration

The Windows program http.exe (download) is designed to show a bit more detail of HTTP than is revealed by conventional Web browsers.

Type a URL into the "URL" edit box and press Enter or click on the "Get" button.

One or more of the edit boxes below the bevel (which are read-only) will be filled in automatically with information arising out of your request.

The contents of the "Sent header" box are fairly constant, with only the pathname and host varying. For example, if you entered the URL http://publish.uwo.ca/~craven/, the sent header would be

GET /~craven/ HTTP/1.0
Host: publish.uwo.ca
Accept: www/source, text/html, video/mpeg, image/jpeg, image/x-tiff
Accept: image/x-rgb, image/x-xbm, image/gif, */*, application/postscript
Content-type: application/x-www-form-urlencoded

The "Events" box shows a log of some of the events that take place in the HTTP interaction. The first part of each line shows the time in seconds after the initial request. A simple example is

     0.0: Host resolved
     0.0: Connecting to 129.100.0.45
     0.0: Packet 1 received, 2852 bytes
     0.0: Disconnected

If the file is successfully downloaded, the "Header" box should show the HTTP header lines; for example,

HTTP/1.1 200 OK
Server: Sun-ONE-Web-Server/6.1
Date: Fri, 13 Apr 2007 19:07:01 GMT
Content-length: 2852
Content-type: text/html
Last-modified: Thu, 12 Apr 2007 19:03:22 GMT
Accept-ranges: bytes
Connection: close
If the page delivered appears to be "headerless", a warning message will pop up, and the "Header" box will be empty.

Finally, the "Body" box should show the file contents (the whole contents of an HTML file, not just the body element). HTML files from Unix or Linux servers may display with little black rectangles instead of line breaks. Contrast the HTTP header, where each line always has to end with both a carriage return and a line feed and so displays correctly in Windows. Contents of graphics files and other files containing non-printing characters will usually not show properly; for example, for a GIF file, all you see might be GIF89aß.

The "User-Agent" box can be used to specify a particular user agent in the request header. This will cause some servers to respond differently.

For a Web-based tool with some similar functions, see


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Last updated April 24, 2007.
This page maintained by Prof. Tim Craven
E-mail (text/plain only): craven@uwo.ca
Faculty of Information and Media Studies
University of Western Ontario,
London, Ontario
Canada, N6A 5B7