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

# CURLINFO\_LASTSOCKET(3)

get the last socket used

## NAME

CURLINFO\_LASTSOCKET - get the last socket used

## SYNOPSIS

```
#include <curl/curl.h>
CURLcode curl_easy_getinfo(CURL *handle, CURLINFO_LASTSOCKET, long *socket);
```

## DESCRIPTION

Deprecated since 7.45.0. Use *[CURLINFO\_ACTIVESOCKET(3)](/CURLINFO_ACTIVESOCKET/3.md)* instead.

Pass a pointer to a long to receive the last socket used by this curl session. If the socket is no longer valid, -1 is returned. When you finish working with the socket, you must call *[curl\_easy\_cleanup(3)](/curl_easy_cleanup/3.md)* as usual and let libcurl close the socket and cleanup other resources associated with the handle. This is typically used in combination with *[CURLOPT\_CONNECT\_ONLY(3)](/CURLOPT_CONNECT_ONLY/3.md)*.

NOTE: this API is deprecated since it is not working on win64 where the SOCKET type is 64 bits large while its 'long' is 32 bits. Use the *[CURLINFO\_ACTIVESOCKET(3)](/CURLINFO_ACTIVESOCKET/3.md)* instead, if possible.

## PROTOCOLS

All

## EXAMPLE

```
int main(void)
{
  CURL *curl = curl_easy_init();
  if(curl) {
    CURLcode res;
    long sockfd; /* does not work on win64! */
    curl_easy_setopt(curl, CURLOPT_URL, "https://example.com");
    /* Do not do the transfer - only connect to host */
    curl_easy_setopt(curl, CURLOPT_CONNECT_ONLY, 1L);
    res = curl_easy_perform(curl);
    /* Extract the socket from the curl handle */
    res = curl_easy_getinfo(curl, CURLINFO_LASTSOCKET, &sockfd);
    if(res != CURLE_OK) {
      printf("Error: %s\n", curl_easy_strerror(res));
      return 1;
    }
  }
}
```

## AVAILABILITY

Added in 7.15.2

## RETURN VALUE

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

## SEE ALSO

[**CURLINFO\_ACTIVESOCKET**(3)](/CURLINFO_ACTIVESOCKET/3.md), [**CURLOPT\_CONNECT\_ONLY**(3)](/CURLOPT_CONNECT_ONLY/3.md), [**curl\_easy\_getinfo**(3)](/curl_easy_getinfo/3.md), [**curl\_easy\_setopt**(3)](/curl_easy_setopt/3.md)