curl_ws_send - send WebSocket data
#include <curl/easy.h>
CURLcode curl_ws_send(CURL *curl, const void *buffer, size_t buflen,
size_t *sent, curl_off_t fragsize,
unsigned int flags);
This function call is EXPERIMENTAL.
Send the specific message fragment over an established WebSocket connection. The
buffer holds the data to send and it is
buflen number of payload
bytes in that memory area.
sent is returned as the number of payload bytes actually sent.
To send a (huge) fragment using multiple calls with partial content per invoke,
set the
CURLWS_OFFSET bit and the
fragsize argument as the total
expected size for the first part, then set the
CURLWS_OFFSET with a
zero
fragsize for the following parts.
If not sending a partial fragment or if this is raw mode,
fragsize should
be set to zero.
If
CURLWS_RAW_MODE is enabled in
CURLOPT_WS_OPTIONS(3), the
flags argument should be set to 0.
To send a message consisting of multiple frames, set the
CURLWS_CONT bit
in all frames except the final one.
- CURLWS_TEXT
- The buffer contains text data. Note that this makes a
difference to WebSocket but libcurl itself will not make any verification
of the content or precautions that you actually send valid UTF-8
content.
- CURLWS_BINARY
- This is binary data.
- CURLWS_CONT
- This is not the final fragment of the message, which
implies that there will be another fragment coming as part of the same
message where this bit is not set.
- CURLWS_CLOSE
- Close this transfer.
- CURLWS_PING
- This is a ping.
- CURLWS_PONG
- This is a pong.
- CURLWS_OFFSET
- The provided data is only a partial fragment and there will
be more in a following call to curl_ws_send(). When sending only a
piece of the fragment like this, the fragsize must be provided with
the total expected fragment size in the first call and it needs to be zero
in subsequent calls.
Added in 7.86.0.
curl_easy_setopt(3),
curl_easy_perform(3),
curl_easy_getinfo(3),
curl_ws_recv(3)