curl_easy_recv(3) libcurl Manual curl_easy_recv(3)NAMEcurl_easy_recv - receives raw data on an "easy" connection
SYNOPSIS
#include <curl/easy.h>
CURLcode curl_easy_recv( CURL *curl, void *buffer, size_t buflen,
size_t *n);
DESCRIPTION
This function receives raw data from the established connection. You
may use it together with curl_easy_send(3) to implement custom proto‐
cols using libcurl. This functionality can be particularly useful if
you use proxies and/or SSL encryption: libcurl will take care of proxy
negotiation and connection set-up.
buffer is a pointer to your buffer that will get the received data.
buflen is the maximum amount of data you can get in that buffer. The
variable n points to will receive the number of received bytes.
To establish the connection, set CURLOPT_CONNECT_ONLY option before
calling curl_easy_perform(3). Note that curl_easy_recv(3) does not work
on connections that were created without this option.
You must ensure that the socket has data to read before calling
curl_easy_recv(3), otherwise the call will return CURLE_AGAIN - the
socket is used in non-blocking mode internally. Use curl_easy_get‐
info(3) with CURLINFO_LASTSOCKET to obtain the socket; use your operat‐
ing system facilities like select(2) to check if it has any data you
can read.
AVAILABILITY
Added in 7.18.2.
RETURN VALUE
On success, returns CURLE_OK, stores the received data into buffer, and
the number of bytes it actually read into *n.
On failure, returns the appropriate error code.
If there is no data to read, the function returns CURLE_AGAIN. Use your
operating system facilities to wait until the data is ready, and retry.
Reading exactly 0 bytes would indicate a closed connection.
If there's no socket available to use from the previous transfer, this
function returns CURLE_UNSUPPORTED_PROTOCOL.
EXAMPLE
See sendrecv.c in docs/examples directory for usage example.
SEE ALSOcurl_easy_setopt(3), curl_easy_perform(3), curl_easy_getinfo(3),
curl_easy_send(3)libcurl 7.18.2 29 April 2008 curl_easy_recv(3)