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<table width="100%" summary="page for curlPerform {RCurl}"><tr><td>curlPerform {RCurl}</td><td style="text-align: right;">R Documentation</td></tr></table>

<h2>Perform the HTTP query</h2>

<h3>Description</h3>

<p>These function causes the HTTP query, that has been specified
via the different options in this and other calls, to be sent and processed.
Unlike in curl itself,
for <code>curlPerform</code> one can specify all the options
in this call as an atomic invocation.
This avoids having to set the options and then perform
the action. Instead, this is all done in one call.
</p>
<p>For <code>curlMultiPerform</code>, one must add the relevant
<code><a href="CURLHandle-class.html">CURLHandle-class</a></code> objects to the
<code><a href="MultiCURLHandle-class.html">MultiCURLHandle-class</a></code> objects
before issuing the call to <code>curlMultiPerform</code>.
</p>

<h3>Usage</h3>

<pre>
curlPerform(..., .opts = list(), curl = getCurlHandle(), .encoding = integer())
curlMultiPerform(curl, multiple = TRUE)
</pre>

<h3>Arguments</h3>

<table summary="R argblock">
<tr valign="top"><td><code>curl</code></td>
<td>
<p>for <code>curlPerform</code>, this is the <code>CURLHandle</code>
object giving the structure for the
options  and that will process the command.
For <code>curlMultiPerform</code>, this is an object of class
code <code><a href="MultiCURLHandle-class.html">MultiCURLHandle-class</a></code>.</p>
</td></tr>
<tr valign="top"><td><code>...</code></td>
<td>
<p>a named list of curl options to set after the handle has
been created.</p>
</td></tr>
<tr valign="top"><td><code>.opts</code></td>
<td>
<p>a named list or <code>CURLOptions</code> object identifying the
curl options for the handle. This is merged with the values of ...
to create the actual options for the curl handle in the request.</p>
</td></tr>
<tr valign="top"><td><code>multiple</code></td>
<td>
<p>a logical value. If <code>TRUE</code> and the internal call
to <code>curl_multi_perform</code> returns a value that indicates there is
still data available from one of the HTTP responses, we call
<code>curl_multi_perform</code> repeatedly until there is no more data
available  at that time. If this is <code>FALSE</code>, we call
<code>curl_multi_perform</code> once and return, regardless of whether
there is more data available. This is convenient if we want to limit
the time spent in the call to <code>curlMultiPerform</code>.
</p>
</td></tr>
<tr valign="top"><td><code>.encoding</code></td>
<td>
<p>an integer or a string that explicitly identifies the
encoding of the content that is returned by the HTTP server in its
response to our query. The possible strings are
&lsquo;UTF-8&rsquo; or &lsquo;ISO-8859-1&rsquo;
and the integers should be specified symbolically
as  <code>CE_UTF8</code> and <code>CE_LATIN1</code>.
Note that, by default, the package attempts to process the header of
the HTTP response to determine the encoding. This argument is used
when such information is erroneous and the caller knows the correct
encoding.
</p>
<p>Note that the encoding argument is not a regular libcurl option and
is handled specially by RCurl. But as a result, it is not unset
in subsequent uses of the curl handle (<code>curl</code>).
</p>
</td></tr>
</table>

<h3>Value</h3>

<p>A integer value indicating the status of the request.
This should be 0 as other errors will generate
errors.
</p>

<h3>Author(s)</h3>

<p>Duncan Temple Lang</p>

<h3>References</h3>

<p>Curl homepage <a href="http://curl.haxx.se">http://curl.haxx.se</a></p>

<p><code><a href="getURL.html">getURL</a></code>
<code><a href="postForm.html">postForm</a></code>
<code><a href="postForm.html">getForm</a></code>
<code><a href="curlSetOpt.html">curlSetOpt</a></code>
</p>

<h3>Examples</h3>

<pre>
if(url.exists("http://www.omegahat.net/RCurl")) withAutoprint({
  h = basicTextGatherer()
  curlPerform(url = "http://www.omegahat.net/RCurl", writefunction = h$update)
   # Now read the text that was cumulated during the query response.
  cat(h$value())
})

## this no longer exists
if(url.exists("http://services.soaplite.com/hibye.cgi")) withAutoprint({
     # SOAP request
  body = '&lt;?xml version="1.0" encoding="UTF-8"?&gt;\
&lt;SOAP-ENV:Envelope SOAP-ENV:encodingStyle="http://schemas.xmlsoap.org/soap/encoding/" \
                   xmlns:SOAP-ENV="http://schemas.xmlsoap.org/soap/envelope/" \
                   xmlns:xsd="http://www.w3.org/1999/XMLSchema" \
                   xmlns:SOAP-ENC="http://schemas.xmlsoap.org/soap/encoding/" \
                   xmlns:xsi="http://www.w3.org/1999/XMLSchema-instance"&gt;\
  &lt;SOAP-ENV:Body&gt;\
       &lt;namesp1:hi xmlns:namesp1="http://www.soaplite.com/Demo"/&gt;\
  &lt;/SOAP-ENV:Body&gt;\
&lt;/SOAP-ENV:Envelope&gt;\n'

h$reset()
  curlPerform(url = "http://services.soaplite.com/hibye.cgi",
              httpheader=c(Accept="text/xml", Accept="multipart/*",
                           SOAPAction='"http://www.soaplite.com/Demo#hi"',
                           'Content-Type' = "text/xml; charset=utf-8"),
              postfields=body,
              writefunction = h$update,
              verbose = TRUE
             )

body = h$value()

})

# Using a C routine as the reader of the body of the response.
if(url.exists("http://www.omegahat.net/RCurl/index.html")) withAutoprint({
  routine = getNativeSymbolInfo("R_internalWriteTest", PACKAGE = "RCurl")$address
  curlPerform(URL = "http://www.omegahat.net/RCurl/index.html",
              writefunction = routine)
})
</pre>

<hr /><div style="text-align: center;">[Package <em>RCurl</em> version 1.98-1.2 <a href="00Index.html">Index</a>]</div>
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