EVOLUTION-MANAGER
Edit File: HEAD.html
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><title>R: Get url HEADers.</title> <meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> <link rel="stylesheet" type="text/css" href="R.css" /> </head><body> <table width="100%" summary="page for HEAD {httr}"><tr><td>HEAD {httr}</td><td style="text-align: right;">R Documentation</td></tr></table> <h2>Get url HEADers.</h2> <h3>Description</h3> <p>Get url HEADers. </p> <h3>Usage</h3> <pre> HEAD(url = NULL, config = list(), ..., handle = NULL) </pre> <h3>Arguments</h3> <table summary="R argblock"> <tr valign="top"><td><code>url</code></td> <td> <p>the url of the page to retrieve</p> </td></tr> <tr valign="top"><td><code>config</code></td> <td> <p>Additional configuration settings such as http authentication (<code><a href="authenticate.html">authenticate()</a></code>), additional headers (<code><a href="add_headers.html">add_headers()</a></code>), cookies (<code><a href="set_cookies.html">set_cookies()</a></code>) etc. See <code><a href="config.html">config()</a></code> for full details and list of helpers.</p> </td></tr> <tr valign="top"><td><code>...</code></td> <td> <p>Further named parameters, such as <code>query</code>, <code>path</code>, etc, passed on to <code><a href="modify_url.html">modify_url()</a></code>. Unnamed parameters will be combined with <code><a href="config.html">config()</a></code>.</p> </td></tr> <tr valign="top"><td><code>handle</code></td> <td> <p>The handle to use with this request. If not supplied, will be retrieved and reused from the <code><a href="handle_pool.html">handle_pool()</a></code> based on the scheme, hostname and port of the url. By default <span class="pkg">httr</span> requests to the same scheme/host/port combo. This substantially reduces connection time, and ensures that cookies are maintained over multiple requests to the same host. See <code><a href="handle_pool.html">handle_pool()</a></code> for more details.</p> </td></tr> </table> <h3>Value</h3> <p>A <code><a href="response.html">response()</a></code> object. </p> <h3>RFC2616</h3> <p>The HEAD method is identical to GET except that the server MUST NOT return a message-body in the response. The metainformation contained in the HTTP headers in response to a HEAD request SHOULD be identical to the information sent in response to a GET request. This method can be used for obtaining metainformation about the entity implied by the request without transferring the entity-body itself. This method is often used for testing hypertext links for validity, accessibility, and recent modification. </p> <p>The response to a HEAD request MAY be cacheable in the sense that the information contained in the response MAY be used to update a previously cached entity from that resource. If the new field values indicate that the cached entity differs from the current entity (as would be indicated by a change in Content-Length, Content-MD5, ETag or Last-Modified), then the cache MUST treat the cache entry as stale. </p> <h3>See Also</h3> <p>Other http methods: <code><a href="BROWSE.html">BROWSE</a>()</code>, <code><a href="DELETE.html">DELETE</a>()</code>, <code><a href="GET.html">GET</a>()</code>, <code><a href="PATCH.html">PATCH</a>()</code>, <code><a href="POST.html">POST</a>()</code>, <code><a href="PUT.html">PUT</a>()</code>, <code><a href="VERB.html">VERB</a>()</code> </p> <h3>Examples</h3> <pre> HEAD("http://google.com") headers(HEAD("http://google.com")) </pre> <hr /><div style="text-align: center;">[Package <em>httr</em> version 1.4.2 <a href="00Index.html">Index</a>]</div> </body></html>