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.TH curl_easy_send 3 "29 April 2008" "libcurl 7.18.2" "libcurl Manual"
curl_easy_send - sends raw data over an "easy" connection
.B #include <curl/easy.h>
.BI "CURLcode curl_easy_send( CURL *" curl ", const void *" buffer ","
.BI " size_t " buflen ", size_t *" n ");"
This function sends arbitrary data over the established connection. You may
use it together with \fIcurl_easy_recv(3)\fP 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.
\fBbuffer\fP is a pointer to the data of length \fBbuflen\fP that you want sent.
The variable \fBn\fP points to will receive the number of sent bytes.
To establish the connection, set \fICURLOPT_CONNECT_ONLY(3)\fP option before
calling \fIcurl_easy_perform(3)\fP or \fIcurl_multi_perform(3)\fP. Note that
\fIcurl_easy_send(3)\fP will not work on connections that were created without
this option.
The call will return \fBCURLE_AGAIN\fP if it's not possible to send data right
now - the socket is used in non-blocking mode internally. When
\fBCURLE_AGAIN\fP is returned, use your operating system facilities like
\fIselect(2)\fP to wait until the socket is writable. The socket may be
obtained using \fIcurl_easy_getinfo(3)\fP with \fICURLINFO_ACTIVESOCKET(3)\fP.
Furthermore if you wait on the socket and it tells you it's writable,
\fIcurl_easy_send(3)\fP may return \fBCURLE_AGAIN\fP if the only data that was
sent was for internal SSL processing, and no other data could be sent.
Added in 7.18.2.
On success, returns \fBCURLE_OK\fP and stores the number of bytes actually
sent into \fB*n\fP. Note that this may very well be less than the amount you
wanted to send.
On failure, returns the appropriate error code.
This function may return \fBCURLE_AGAIN\fP. In this case, use your operating
system facilities to wait until the socket is writable, and retry.
If there's no socket available to use from the previous transfer, this function
See \fBsendrecv.c\fP in \fBdocs/examples\fP directory for usage example.
.BR curl_easy_setopt "(3), " curl_easy_perform "(3), " curl_easy_getinfo "(3), "
.BR curl_easy_recv "(3) "