curl_easy_send

Section: libcurl Manual (3)
Updated: 29 April 2008
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NAME

curl_easy_send - sends raw data over an "easy" connection

SYNOPSIS

#include <curl/easy.h>

CURLcode curl_easy_send( CURL *curl, const void *buffer, size_t buflen, size_t *n);

DESCRIPTION

This function sends arbitrary data over the established connection. You may use it together with curl_easy_recv(3) to implement custom protocols 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 the data of length buflen that you want sent. The variable n points to will receive the number of sent bytes.

To establish the connection, set CURLOPT_CONNECT_ONLY option before calling curl_easy_perform(3). Note that curl_easy_send(3) will not work on connections that were created without this option.

You must ensure that the socket is writable before calling curl_easy_send(3), otherwise the call will return CURLE_AGAIN - the socket is used in non-blocking mode internally. Use curl_easy_getinfo(3) with CURLINFO_LASTSOCKET to obtain the socket; use your operating system facilities like select(2) to check if it can be written to.

AVAILABILITY

Added in 7.18.2.

RETURN VALUE

On success, returns CURLE_OK and stores the number of bytes actually sent into *n. Note that this may very well be less than the amount you wanted to send.

On failure, returns the appropriate error code.

EXAMPLE

See sendrecv.c in docs/examples directory for usage example.