curl-w32/docs/libcurl/curl_ws_recv.md

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---
c: Copyright (C) Daniel Stenberg, <daniel.se>, et al.
SPDX-License-Identifier: curl
Title: curl_ws_recv
Section: 3
Source: libcurl
See-also:
- curl_easy_getinfo (3)
- curl_easy_perform (3)
- curl_easy_setopt (3)
- curl_ws_send (3)
- libcurl-ws (3)
---
# NAME
curl_ws_recv - receive WebSocket data
# SYNOPSIS
~~~c
#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.
# EXAMPLE
~~~c
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.