curl_ws_recv(3)            Library Functions Manual            curl_ws_recv(3)

NAME
       curl_ws_recv - receive WebSocket data

SYNOPSIS
       #include <curl/curl.h>

       CURLcode curl_ws_recv(CURL *curl, void *buffer, size_t buflen,
                             size_t *recv, const struct curl_ws_frame **meta);

DESCRIPTION
       This function call is EXPERIMENTAL.

       Retrieves as much as possible of a received WebSocket data fragment
       into the buffer, but not more than buflen bytes. recv is set to the
       number of bytes actually stored.

       If there is more fragment data to deliver than what fits in the
       provided buffer, libcurl returns a full buffer and the application
       needs to call this function again to continue draining the buffer.

       The meta pointer gets set to point to a const struct curl_ws_frame that
       contains information about the received data. See the curl_ws_meta(3)
       for details on that struct.

PROTOCOLS
       WS

EXAMPLE
       int main(void)
       {
         size_t rlen;
         const struct curl_ws_frame *meta;
         char buffer[256];
         CURL *curl = curl_easy_init();
         if(curl) {
           CURLcode res = curl_ws_recv(curl, buffer, sizeof(buffer), &rlen, &meta);
           if(res)
             printf("error: %s\n", curl_easy_strerror(res));
         }
       }

AVAILABILITY
       Added in 7.86.0.

RETURN VALUE
       Returns CURLE_OK if everything is okay, and a non-zero number for
       errors. Returns CURLE_GOT_NOTHING if the associated connection is
       closed.

       Instead of blocking, the function returns CURLE_AGAIN. The correct
       behavior is then to wait for the socket to signal readability before
       calling this function again.

SEE ALSO
       curl_easy_getinfo(3), curl_easy_perform(3), curl_easy_setopt(3),
       curl_ws_send(3), libcurl-ws(3)

libcurl                          April 26 2024                 curl_ws_recv(3)