---
name: "CURLINFO_SSL_ENGINES"
section: "3"
platform: "linux"
package: "curl"
version: "8.23.0-1"
release: "Arch Linux 2026-11-01"
platforms: ["linux", "macos"]
url: "https://new.carta.tech/CURLINFO_SSL_ENGINES"
---

# CURLINFO\_SSL\_ENGINES(3)

an slist of OpenSSL crypto-engines

## NAME

CURLINFO\_SSL\_ENGINES - an slist of OpenSSL crypto-engines

## SYNOPSIS

```
#include <curl/curl.h>
CURLcode curl_easy_getinfo(CURL *handle, CURLINFO_SSL_ENGINES,
                           struct curl_slist **engine_list);
```

## DESCRIPTION

Pass the address of a 'struct curl\_slist \*' to receive a linked-list of OpenSSL crypto-engines supported. Note that engines are normally implemented in separate dynamic libraries. Hence not all the returned engines may be available at runtime. **NOTE:** you must call *[curl\_slist\_free\_all(3)](/curl_slist_free_all/3.md)* on the list pointer once you are done with it, as libcurl does not free this data for you.

## PROTOCOLS

This functionality affects  all TLS based protocols: HTTPS, FTPS, IMAPS, POP3S, SMTPS etc. only

This option works only with the following TLS backends: OpenSSL

## EXAMPLE

```
int main(void)
{
  CURL *curl = curl_easy_init();
  if(curl) {
    CURLcode result;
    struct curl_slist *engines;
    result = curl_easy_getinfo(curl, CURLINFO_SSL_ENGINES, &engines);
    if((result == CURLE_OK) && engines) {
      /* we have a list, free it when done using it */
      curl_slist_free_all(engines);
    }
    curl_easy_cleanup(curl);
  }
}
```

## AVAILABILITY

Added in curl 7.12.3

## RETURN VALUE

*[curl\_easy\_getinfo(3)](/curl_easy_getinfo/3.md)* returns a CURLcode indicating success or error.

CURLE\_OK (0) means everything was OK, non-zero means an error occurred, see *[libcurl-errors(3)](/libcurl-errors/3.md)*.

## SEE ALSO

[**CURLOPT\_SSLENGINE**(3)](/CURLOPT_SSLENGINE/3.md), [**curl\_easy\_getinfo**(3)](/curl_easy_getinfo/3.md), [**curl\_easy\_setopt**(3)](/curl_easy_setopt/3.md)