curl-7.25.0/docs/libcurl/curl_easy_send.3

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.TH curl_easy_send 3 "29 April 2008" "libcurl 7.18.2" "libcurl Manual"
.SH NAME
curl_easy_send - sends raw data over an "easy" connection
.SH SYNOPSIS
.B #include <curl/easy.h>
.sp
.BI "CURLcode curl_easy_send( CURL *" curl ", const void *" buffer ","
.BI " size_t " buflen ", size_t *" n ");"
.ad
.SH DESCRIPTION
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 \fBCURLOPT_CONNECT_ONLY\fP option before
calling \fIcurl_easy_perform(3)\fP. Note that \fIcurl_easy_send(3)\fP will not
work on connections that were created without this option.

You must ensure that the socket is writable before calling
\fIcurl_easy_send(3)\fP, otherwise the call will return \fBCURLE_AGAIN\fP -
the socket is used in non-blocking mode internally. Use
\fIcurl_easy_getinfo(3)\fP with \fBCURLINFO_LASTSOCKET\fP to obtain the
socket; use your operating system facilities like \fIselect(2)\fP to check if
it can be written to.
.SH AVAILABILITY
Added in 7.18.2.
.SH RETURN VALUE
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.
.SH EXAMPLE
See \fBsendrecv.c\fP in \fBdocs/examples\fP directory for usage example.
.SH "SEE ALSO"
.BR curl_easy_setopt "(3), " curl_easy_perform "(3), " curl_easy_getinfo "(3), "
.BR curl_easy_recv "(3) "