you also might want to take a look at using ethereal (GUI) and/or tethereal (CLI) as replacements for tcpdump. It's packet selection mechanism is able to analyze HTTP, so you can do your selection of traffic there, for instance this selects all GET and HEAD requests from a live capture on one of my ethernet interface: 
tethereal -i eth1 -R'http.request.method == "GET" || http.request.meth
+od == "HEAD"'

[download]
outputs: 
  7.518730 66.27.72.141 -> 192.172.226.123 HTTP GET / HTTP/1.1
  7.616699 66.27.72.141 -> 192.172.226.123 HTTP GET /HOME/images/nav_1
+_1_HOME.gif HTTP/1.1
  7.638719 66.27.72.141 -> 192.172.226.123 HTTP GET /HOME/images/nav_2
+_1_HOME_overview.gif HTTP/1.1
  7.641536 66.27.72.141 -> 192.172.226.123 HTTP GET /images/nav_1_2_GL
+OBAL_globe.gif HTTP/1.1
  7.670158 66.27.72.141 -> 192.172.226.123 HTTP GET /images/nav_2_2_GL
+OBAL_globe.gif HTTP/1.1
  7.694446 66.27.72.141 -> 192.172.226.123 HTTP GET /HOME/images/nav_3
+_1_HOME_overview.gif HTTP/1.1
  7.714087 66.27.72.141 -> 192.172.226.123 HTTP GET /HOME/images/nav_3
+_2_HOME_globe.gif HTTP/1.1

[download]
replace -i <iface> with -r <file> to read from file.

In reply to Re: converting tcpdump output by eXile
in thread converting tcpdump output by RnC

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post, it's "PerlMonks-approved HTML":


  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.