NAME

curl_version_info - returns run-time libcurl version info

SYNOPSIS

#include <curl/curl.h> curl_version_info_data *curl_version_info( CURLversion age);

DESCRIPTION

Returns a pointer to a filled in static struct with information about various features in the running version of libcurl. age should be set to the version of this functionality by the time you write your program. This way, libcurl will always return a proper struct that your program understands, while programs in the future might get a different struct. CURLVERSION_NOW will be the most recent one for the library you have installed:
data = curl_version_info(CURLVERSION_NOW); Applications should use this information to judge if things are possible to do or not, instead of using compile-time checks, as dynamic/DLL libraries can be changed independent of applications. The curl_version_info_data struct looks like this

typedef struct {
  CURLversion age;          /* see description below */

  /* when 'age' is 0 or higher, the members below also exist: */
  const char *version;      /* human readable string */
  unsigned int version_num; /* numeric representation */
  const char *host;         /* human readable string */
  int features;             /* bitmask, see below */
  char *ssl_version;        /* human readable string */
  long ssl_version_num;     /* not used, always zero */
  const char *libz_version; /* human readable string */
  const char * const *protocols; /* protocols */

  /* when 'age' is 1 or higher, the members below also exist: */
  const char *ares;         /* human readable string */
  int ares_num;             /* number */

  /* when 'age' is 2 or higher, the member below also exists: */
  const char *libidn;       /* human readable string */

  /* when 'age' is 3 or higher (7.16.1 or later), the members below also
     exist  */
  int iconv_ver_num;       /* '_libiconv_version' if iconv support enabled */

  const char *libssh_version; /* human readable string */

  /* when 'age' is 4 or higher (7.57.0 or later), the members below also
     exist  */
  unsigned int brotli_ver_num; /* Numeric Brotli version
                                  (MAJOR << 24) | (MINOR << 12) | PATCH */
  const char *brotli_version; /* human readable string. */

  /* when 'age is CURLVERSION_SIXTH or alter (7.66.0 or later), these fields
     also exist */
  unsigned int nghttp2_ver_num; /* Numeric nghttp2 version
                                   (MAJOR << 16) | (MINOR << 8) | PATCH */
  const char *nghttp2_version; /* human readable string. */

  const char *quic_version;    /* human readable quic (+ HTTP/3) library +
                                  version or NULL */

} curl_version_info_data;

age describes what the age of this struct is. The number depends on how new the libcurl you're using is. You are however guaranteed to get a struct that you have a matching struct for in the header, as you tell libcurl your "age" with the input argument. version is just an ascii string for the libcurl version. version_num is a 24 bit number created like this: <8 bits major number> | <8 bits minor number> | <8 bits patch number>. Version 7.9.8 is therefore returned as 0x070908. host is an ascii string showing what host information that this libcurl was built for. As discovered by a configure script or set by the build environment. features can have none, one or more bits set, and the currently defined bits are: ssl_version is an ASCII string for the TLS library name + version used. If libcurl has no SSL support, this is NULL. For example "Schannel", "SecureTransport" or "OpenSSL/1.1.0g". ssl_version_num is always 0. libz_version is an ASCII string (there is no numerical version). If libcurl has no libz support, this is NULL. protocols is a pointer to an array of char * pointers, containing the names protocols that libcurl supports (using lowercase letters). The protocol names are the same as would be used in URLs. The array is terminated by a NULL entry.

RETURN VALUE

A pointer to a curl_version_info_data struct.

SEE ALSO

curl_version(3)