CURLINFO\_SSL\_ENGINES(3) Library Functions Manual CURLINFO\_SSL\_ENGINES(3)

# [NAME](#NAME)

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

# [SYNOPSIS](#SYNOPSIS)

```
#include <curl/curl.h>
CURLcode curl_easy_getinfo(CURL *handle, CURLINFO_SSL_ENGINES,


                           struct curl_slist **engine_list);
```

# [DESCRIPTION](#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)*](/man/os/curl/curl_slist_free_all.3) on the list pointer once you are done with it, as libcurl does not free this data for you.

# [PROTOCOLS](#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](#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](#AVAILABILITY)

Added in curl 7.12.3

# [RETURN VALUE](#RETURN_VALUE)

[*curl\_easy\_getinfo(3)*](/man/os/curl/curl_easy_getinfo.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)*](/man/os/curl/libcurl-errors.3).

# [SEE ALSO](#SEE_ALSO)

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

2026-10-22 libcurl

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Document: CURLINFO_SSL_ENGINES(3) from curl 8.23.0-r2 (Chainguard OS)
Source: https://github.com/curl/curl.git