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curl (version 0.9.3)

curl_fetch_memory: Fetch the contents of a URL

Description

Low-level bindings to write data from a URL into memory, disk or a callback function. These are mainly intended for httr, most users will be better off using the curl or curl_download function, or the http specific wrappers in the httr package.

Usage

curl_fetch_memory(url, handle = new_handle())

curl_fetch_disk(url, path, handle = new_handle())

curl_fetch_stream(url, fun, handle = new_handle())

Arguments

url
A character string naming the URL of a resource to be downloaded.
handle
a curl handle object
path
Path to save results
fun
Callback function. Should have one argument, which will be a raw vector.

Details

The curl_fetch functions automatically raise an error upon protocol problems (network, disk, ssl) but do not implement application logic. For example for you need to check the status code of http requests yourself in the response, and deal with it accordingly.

Examples

Run this code
# Load in memory
res <- curl_fetch_memory("http://httpbin.org/cookies/set?foo=123&bar=ftw")
res$content

# Save to disk
res <- curl_fetch_disk("http://httpbin.org/stream/10", tempfile())
res$content
readLines(res$content)

# Stream with callback
res <- curl_fetch_stream("http://httpbin.org/stream/20", function(x){
  cat(rawToChar(x))
})

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