curl/docs/examples/websocket-cb.c
Daniel Stenberg 78886afb50
ws: make the curl_ws_meta() return pointer a const
The returned info is read-only for the user.

Closes #11261
2023-06-07 23:37:21 +02:00

69 lines
2.2 KiB
C

/***************************************************************************
* _ _ ____ _
* Project ___| | | | _ \| |
* / __| | | | |_) | |
* | (__| |_| | _ <| |___
* \___|\___/|_| \_\_____|
*
* Copyright (C) Daniel Stenberg, <daniel@haxx.se>, et al.
*
* This software is licensed as described in the file COPYING, which
* you should have received as part of this distribution. The terms
* are also available at https://curl.se/docs/copyright.html.
*
* You may opt to use, copy, modify, merge, publish, distribute and/or sell
* copies of the Software, and permit persons to whom the Software is
* furnished to do so, under the terms of the COPYING file.
*
* This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
* KIND, either express or implied.
*
* SPDX-License-Identifier: curl
*
***************************************************************************/
/* <DESC>
* WebSocket download-only using write callback
* </DESC>
*/
#include <stdio.h>
#include <curl/curl.h>
static size_t writecb(char *b, size_t size, size_t nitems, void *p)
{
CURL *easy = p;
size_t i;
const struct curl_ws_frame *frame = curl_ws_meta(easy);
fprintf(stderr, "Type: %s\n", frame->flags & CURLWS_BINARY ?
"binary" : "text");
fprintf(stderr, "Bytes: %u", (unsigned int)(nitems * size));
for(i = 0; i < nitems; i++)
fprintf(stderr, "%02x ", (unsigned char)b[i]);
return nitems;
}
int main(void)
{
CURL *curl;
CURLcode res;
curl = curl_easy_init();
if(curl) {
curl_easy_setopt(curl, CURLOPT_URL, "wss://example.com");
curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, writecb);
/* pass the easy handle to the callback */
curl_easy_setopt(curl, CURLOPT_WRITEDATA, curl);
/* Perform the request, res will get the return code */
res = curl_easy_perform(curl);
/* Check for errors */
if(res != CURLE_OK)
fprintf(stderr, "curl_easy_perform() failed: %s\n",
curl_easy_strerror(res));
/* always cleanup */
curl_easy_cleanup(curl);
}
return 0;
}