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CURLOPT_WS_OPTIONS

Section: C Library Functions (3)
Updated: 202-0-19
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NAME

CURLOPT_WS_OPTIONS - WebSocket behavior options

SYNOPSIS

#include <curl/curl.h>

CURLcode curl_easy_setopt(CURL *handle, CURLOPT_WS_OPTIONS, long bitmask);

DESCRIPTION

Pass a long with a bitmask to tell libcurl about specific WebSocket behaviors.

To detach a WebSocket connection and use the curl_ws_send(3) and curl_ws_recv(3) functions after the HTTP upgrade procedure, set the CURLOPT_CONNECT_ONLY(3) option to 2L.

Available bits in the bitmask

CURLWS_RAW_MODE (1): Deliver "raw" WebSocket traffic to the CURLOPT_WRITEFUNCTION(3) callback. Read "raw" WebSocket traffic from the CURLOPT_READFUNCTION(3) callback.
In raw mode, libcurl does not handle pings or any other frame for the application.
CURLWS_NOAUTOPONG (2): Disable the automatic reply to PING messages. This means users must send a PONG message with curl_ws_send(3). This feature is added with version 8.14.0.

DEFAULT

PROTOCOLS

This functionality affects ws only

EXAMPLE

int main(void)
{
  CURL *curl = curl_easy_init();
  if(curl) {
    CURLcode result;
    curl_easy_setopt(curl, CURLOPT_URL, "ws://example.com/");
    /* tell curl we deal with all the WebSocket logic ourselves */
    curl_easy_setopt(curl, CURLOPT_WS_OPTIONS, CURLWS_RAW_MODE);
    result = curl_easy_perform(curl);
    curl_easy_cleanup(curl);
  }
}

HISTORY

CURLWS_RAW_MODE and CURLWS_NOAUTOPONG macros became long types in 8.16.0, prior to this version a long cast was necessary when passed to curl_easy_setopt(3).

AVAILABILITY

Added in curl 7.86.0

RETURN VALUE

curl_easy_setopt(3) returns a CURLcode indicating success or error.

CURLE_OK (0) means everything was OK, non-zero means an error occurred, see libcurl-errors(3).