CURLOPT_EXPECT_100_TIMEOUT_MS(3)

CURLOPT_EXPECT_100_TIMEOUT_MS3

Timeout for expect: 100-continue response

Usage

#include <curl/curl.h>
CURLcode curl_easy_setopt(CURL *handle, CURLOPT_EXPECT_100_TIMEOUT_MS,
                          long milliseconds);

Overview

Pass a long to tell libcurl the number of milliseconds to wait for a server response with the HTTP status 100 (Continue), 417 (Expectation Failed) or similar after sending an HTTP request containing an Expect: 100-continue header. If this times out before a response is received, the request body is sent anyway.

Default

1000 milliseconds

Protocols

This functionality affects http only

Examples

int main(void)
{
  CURL *curl = curl_easy_init();
  if(curl) {
    CURLcode result;
    curl_easy_setopt(curl, CURLOPT_URL, "https://example.com");
    /* wait 3 seconds for 100-continue */
    curl_easy_setopt(curl, CURLOPT_EXPECT_100_TIMEOUT_MS, 3000L);
    result = curl_easy_perform(curl);
    curl_easy_cleanup(curl);
  }
}

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).

Releases

7 releases since Debian 8 (Jessie); the text changed 6 times.

  1. 8
  2. 9
  3. 10
  4. 11
  5. 12
  6. 13
  7. Arch

Availability

Added in curl 7.36.0

From curl 8.23.0-1 in Arch Linux 2026-11-01. Parsed by carta from the page's man source.