chrome omnibox how to add the search on domain

Yes it's possible.I did this for my blog.

 <link rel="search" type="application/opensearchdescription+xml" title="The Sheng Blog" href="/resources/opensearch.php"/>

opensearch.php looks likes this:

 <?xml version="1.0"?> <OpenSearchDescription xmlns="http://a9.com/-/spec/opensearch/1.1/">     <ShortName>The Sheng Blog (Beta)</ShortName>     <Description>The Sheng Blog Search</Description>     <Developer>Sheng Slogar</Developer>     <LongName>Search the entire Sheng Blog</LongName>     <InputEncoding>UTF-8</InputEncoding>     <OutputEncoding>UTF-8</OutputEncoding>     <Query role="example" searchTerms="code"/>     <SyndicationRight>open</SyndicationRight>     <AdultContent>false</AdultContent>     <Language>en-us</Language>     <Contact>contact@theshengblogg.comule.com</Contact>     <Tags>code posts tutorials ideas playground</Tags>     <Image width="16" height="16" type="image/x-icon">data:/ico;base64,AAABA...(Icon in base64)</Image>     <Url type="text/html" template="http://theshengblogg.comule.com/search.php?s={searchTerms}"></Url>     <Url type="application/x-suggestions+json" method="GET" template="http://theshengblogg.comule.com/autocomplete.php?search={searchTerms}&json=true"/> </OpenSearchDescription>

I learned this from http://www.opensearch.org/Specifications/OpenSearch/1.1. The autocomplete part is optional. Return it in JSON format.

For example, if you search "a", return ["a","about","across","all","and"]. (Notice I put your query in the array as item 0.)

My autocomplete only seems to work in Firefox. This might be something with my sub domain.I also couldn't get it to work in IE or Chrome.

http://dev.chromium.org/tab-to-search has the information on how to do it, potentially you could use a chrome addon to force the page to have the needed code for this to function, but I'm not sure how well such would work.