Provided by: libcurl4-doc_7.88.1-8ubuntu1_all 
NAME
curl_version_info - returns runtime 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.
This function can alter the returned static data as long as curl_global_init has not been
called. It is therefore not thread-safe before libcurl initialization occurs.
The curl_version_info_data struct looks like this
typedef struct {
CURLversion age; /* see description below */
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 CURLVERSION_SECOND or higher, the members below exist */
const char *ares; /* human readable string */
int ares_num; /* number */
/* when 'age' is CURLVERSION_THIRD or higher, the members below exist */
const char *libidn; /* human readable string */
/* when 'age' is CURLVERSION_FOURTH or higher (>= 7.16.1), the members
below exist */
int iconv_ver_num; /* '_libiconv_version' if iconv support enabled */
const char *libssh_version; /* human readable string */
/* when 'age' is CURLVERSION_FIFTH or higher (>= 7.57.0), the members
below 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 higher (>= 7.66.0), the members
below 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 */
/* when 'age' is CURLVERSION_SEVENTH or higher (>= 7.70.0), the members
below exist */
const char *cainfo; /* the built-in default CURLOPT_CAINFO, might
be NULL */
const char *capath; /* the built-in default CURLOPT_CAPATH, might
be NULL */
/* when 'age' is CURLVERSION_EIGHTH or higher (>= 7.71.0), the members
below exist */
unsigned int zstd_ver_num; /* Numeric Zstd version
(MAJOR << 24) | (MINOR << 12) | PATCH */
const char *zstd_version; /* human readable string. */
/* when 'age' is CURLVERSION_NINTH or higher (>= 7.75.0), the members
below exist */
const char *hyper_version; /* human readable string. */
/* when 'age' is CURLVERSION_TENTH or higher (>= 7.77.0), the members
below exist */
const char *gsasl_version; /* human readable string. */
/* when 'age' is CURLVERSION_ELEVENTH or higher (>= 7.87.0), the members
below exist */
const char *const *feature_names; /* Feature names. */
} curl_version_info_data;
age describes what the age of this struct is. The number depends on how new the libcurl
you are 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 is a bit mask representing available features. It can have none, one or more bits
set. The use of this field is deprecated: use feature_names instead. The feature names
description below lists the associated bits.
feature_names is a pointer to an array of string pointers, containing the names of the
features that libcurl supports. The array is terminated by a NULL entry. Currently defined
names are:
"alt-svc"
features mask bit: CURL_VERSION_ALTSVC
HTTP Alt-Svc parsing and the associated options (Added in 7.64.1)
"AsynchDNS"
features mask bit: CURL_VERSION_ASYNCHDNS
libcurl was built with support for asynchronous name lookups, which allows
more exact timeouts (even on Windows) and less blocking when using the multi
interface. (added in 7.10.7)
"brotli"
features mask bit: CURL_VERSION_BROTLI
supports HTTP Brotli content encoding using libbrotlidec (Added in 7.57.0)
"Debug"
features mask bit: CURL_VERSION_DEBUG
libcurl was built with debug capabilities (added in 7.10.6)
"gsasl"
features mask bit: CURL_VERSION_GSASL
libcurl was built with libgsasl and thus with some extra SCRAM-SHA
authentication methods. (added in 7.76.0)
"GSS-API"
features mask bit: CURL_VERSION_GSSAPI
libcurl was built with support for GSS-API. This makes libcurl use provided
functions for Kerberos and SPNEGO authentication. It also allows libcurl to
use the current user credentials without the app having to pass them on.
(Added in 7.38.0)
"HSTS" features mask bit: CURL_VERSION_HSTS
libcurl was built with support for HSTS (HTTP Strict Transport Security)
(Added in 7.74.0)
"HTTP2"
features mask bit: CURL_VERSION_HTTP2
libcurl was built with support for HTTP2. (Added in 7.33.0)
"HTTP3"
features mask bit: CURL_VERSION_HTTP3
HTTP/3 and QUIC support are built-in (Added in 7.66.0)
"HTTPS-proxy"
features mask bit: CURL_VERSION_HTTPS_PROXY
libcurl was built with support for HTTPS-proxy. (Added in 7.52.0)
"IDN" features mask bit: CURL_VERSION_IDN
libcurl was built with support for IDNA, domain names with international
letters. (Added in 7.12.0)
"IPv6" features mask bit: CURL_VERSION_IPV6
supports IPv6
"Kerberos"
features mask bit: CURL_VERSION_KERBEROS5
supports Kerberos V5 authentication for FTP, IMAP, LDAP, POP3, SMTP and
SOCKSv5 proxy. (Added in 7.40.0)
"Largefile"
features mask bit: CURL_VERSION_LARGEFILE
libcurl was built with support for large files. (Added in 7.11.1)
"libz" features mask bit: CURL_VERSION_LIBZ
supports HTTP deflate using libz (Added in 7.10)
"MultiSSL"
features mask bit: CURL_VERSION_MULTI_SSL
libcurl was built with multiple SSL backends. For details, see
curl_global_sslset(3). (Added in 7.56.0)
"NTLM" features mask bit: CURL_VERSION_NTLM
supports HTTP NTLM (added in 7.10.6)
"NTLM_WB"
features mask bit: CURL_VERSION_NTLM_WB
libcurl was built with support for NTLM delegation to a winbind helper.
(Added in 7.22.0)
"PSL" features mask bit: CURL_VERSION_PSL
libcurl was built with support for Mozilla's Public Suffix List. This makes
libcurl ignore cookies with a domain that is on the list. (Added in 7.47.0)
"SPNEGO"
features mask bit: CURL_VERSION_SPNEGO
libcurl was built with support for SPNEGO authentication (Simple and
Protected GSS-API Negotiation Mechanism, defined in RFC 2478.) (added in
7.10.8)
"SSL" features mask bit: CURL_VERSION_SSL
supports SSL (HTTPS/FTPS) (Added in 7.10)
"SSPI" features mask bit: CURL_VERSION_SSPI
libcurl was built with support for SSPI. This is only available on Windows
and makes libcurl use Windows-provided functions for Kerberos, NTLM, SPNEGO
and Digest authentication. It also allows libcurl to use the current user
credentials without the app having to pass them on. (Added in 7.13.2)
"threadsafe"
features mask bit: CURL_VERSION_THREADSAFE
libcurl was built with thread-safety support (Atomic or SRWLOCK) to protect
curl initialization. (Added in 7.84.0) See libcurl-thread(3)
"TLS-SRP"
features mask bit: CURL_VERSION_TLSAUTH_SRP
libcurl was built with support for TLS-SRP (in one or more of the built-in
TLS backends). (Added in 7.21.4)
"TrackMemory"
features mask bit: CURL_VERSION_CURLDEBUG
libcurl was built with memory tracking debug capabilities. This is mainly of
interest for libcurl hackers. (added in 7.19.6)
"Unicode"
features mask bit: CURL_VERSION_UNICODE
libcurl was built with Unicode support on Windows. This makes non-ASCII
characters work in filenames and options passed to libcurl. (Added in
7.72.0)
"UnixSockets"
features mask bit: CURL_VERSION_UNIX_SOCKETS
libcurl was built with support for Unix domain sockets. (Added in 7.40.0)
"zstd" features mask bit: CURL_VERSION_ZSTD
supports HTTP zstd content encoding using zstd library (Added in 7.72.0)
none features mask bit: CURL_VERSION_CONV
libcurl was built with support for character conversions, as provided by the
CURLOPT_CONV_* callbacks. Always 0 since 7.82.0. (Added in 7.15.4)
none features mask bit: CURL_VERSION_GSSNEGOTIATE
supports HTTP GSS-Negotiate (added in 7.10.6, deprecated in 7.38.0)
none features mask bit: CURL_VERSION_KERBEROS4
supports Kerberos V4 (when using FTP). Legacy bit. Deprecated since 7.33.0.
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", "Secure Transport" 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.
EXAMPLE
curl_version_info_data *ver = curl_version_info(CURLVERSION_NOW);
printf("libcurl version %u.%u.%u\n",
(ver->version_num >> 16) & 0xff,
(ver->version_num >> 8) & 0xff,
ver->version_num & 0xff);
AVAILABILITY
Added in 7.10
RETURN VALUE
A pointer to a curl_version_info_data struct.
SEE ALSO
curl_version(3)