---
name: "CURLOPT_EXPECT_100_TIMEOUT_MS"
section: "3"
platform: "macos"
package: "curl"
version: "166.0.0.0.1"
release: "macOS 26.5"
platforms: ["linux", "macos"]
url: "https://new.carta.tech/CURLOPT_EXPECT_100_TIMEOUT_MS"
---

# CURLOPT\_EXPECT\_100\_TIMEOUT\_MS(3)

timeout for Expect: 100-continue response

## NAME

CURLOPT\_EXPECT\_100\_TIMEOUT\_MS - timeout for Expect: 100-continue response

## SYNOPSIS

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

## DESCRIPTION

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

HTTP

## EXAMPLE

```
int main(void)
{
  CURL *curl = curl_easy_init();
  if(curl) {
    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);
    curl_easy_perform(curl);
  }
}
```

## AVAILABILITY

Added in 7.36.0

## RETURN VALUE

Returns CURLE\_OK if the option is supported, and CURLE\_UNKNOWN\_OPTION if not.

## SEE ALSO

[**CURLOPT\_HTTPPOST**(3)](/CURLOPT_HTTPPOST/3.md), [**CURLOPT\_POST**(3)](/CURLOPT_POST/3.md)