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

<h2>Curl connection interface</h2>

<h3>Description</h3>

<p>Drop-in replacement for base <code><a href="../../base/html/connections.html">url</a></code> that supports https, ftps,
gzip, deflate, etc. Default behavior is identical to <code><a href="../../base/html/connections.html">url</a></code>, but
request can be fully configured by passing a custom <code><a href="handle.html">handle</a></code>.
</p>

<h3>Usage</h3>

<pre>
curl(url = "http://httpbin.org/get", open = "", handle = new_handle())
</pre>

<h3>Arguments</h3>

<table summary="R argblock">
<tr valign="top"><td><code>url</code></td>
<td>
<p>character string. See examples.</p>
</td></tr>
<tr valign="top"><td><code>open</code></td>
<td>
<p>character string. How to open the connection if it should be opened
initially. Currently only &quot;r&quot; and &quot;rb&quot; are supported.</p>
</td></tr>
<tr valign="top"><td><code>handle</code></td>
<td>
<p>a curl handle object</p>
</td></tr>
</table>

<h3>Details</h3>

<p>As of version 2.3 curl connections support <code>open(con, blocking = FALSE)</code>.
In this case <code>readBin</code> and <code>readLines</code> will return immediately with data
that is available without waiting. For such non-blocking connections the caller
needs to call <code><a href="../../base/html/connections.html">isIncomplete</a></code> to check if the download has completed
yet.
</p>

<h3>Examples</h3>

<pre>
## Not run: 
con &lt;- curl("https://httpbin.org/get")
readLines(con)

# Auto-opened connections can be recycled
open(con, "rb")
bin &lt;- readBin(con, raw(), 999)
close(con)
rawToChar(bin)

# HTTP error
curl("https://httpbin.org/status/418", "r")

# Follow redirects
readLines(curl("https://httpbin.org/redirect/3"))

# Error after redirect
curl("https://httpbin.org/redirect-to?url=http://httpbin.org/status/418", "r")

# Auto decompress Accept-Encoding: gzip / deflate (rfc2616 #14.3)
readLines(curl("http://httpbin.org/gzip"))
readLines(curl("http://httpbin.org/deflate"))

# Binary support
buf &lt;- readBin(curl("http://httpbin.org/bytes/98765", "rb"), raw(), 1e5)
length(buf)

# Read file from disk
test &lt;- paste0("file://", system.file("DESCRIPTION"))
readLines(curl(test))

# Other protocols
read.csv(curl("ftp://cran.r-project.org/pub/R/CRAN_mirrors.csv"))
readLines(curl("ftps://test.rebex.net:990/readme.txt"))
readLines(curl("gopher://quux.org/1"))

# Streaming data
con &lt;- curl("http://jeroen.github.io/data/diamonds.json", "r")
while(length(x &lt;- readLines(con, n = 5))){
  print(x)
}

# Stream large dataset over https with gzip
library(jsonlite)
con &lt;- gzcon(curl("https://jeroen.github.io/data/nycflights13.json.gz"))
nycflights &lt;- stream_in(con)

## End(Not run)

</pre>

<hr /><div style="text-align: center;">[Package <em>curl</em> version 4.3 <a href="00Index.html">Index</a>]</div>
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