curl_version_info.3

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.\" $Id: curl_version_info.3,v 1.5 2003/09/19 12:56:22 bagder Exp $
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.TH curl_version_info 3 "19 Sep 2003" "libcurl 7.10.8" "libcurl Manual"
.SH NAME
curl_version_info - returns run-time libcurl version info
.SH SYNOPSIS
.B #include <curl/curl.h>
.sp
.BI "curl_version_info_data *curl_version_info( CURLversion "type ");"
.ad
.SH DESCRIPTION
Returns a pointer to a filled in struct with information about various
run-time features in libcurl. \fItype\fP 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 an 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

.nf
typedef struct {
  CURLversion age;          /* 0 - this kind of struct */
  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;     /* number */
  char *libz_version;       /* human readable string */
  const char *protocols[];  /* list of protocols */
} curl_version_info_data;
.fi

\fIage\fP describes what kind of struct this is. It is always 0 now. In a
future libcurl, if this struct changes, this age counter may be increased, and
then the struct for number 1 will look different (except for this first struct
field).

\fIversion\fP is just an ascii string for the libcurl version.

\fIversion_num\fP is a 6 digit hexadecimal number created like this: <2 digits
major number> | <2 digits minor number> | <2 digits patch number>. Version
7.9.8 is therefore returned as 0x070908.

\fIhost\fP 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.

\fIfeatures\fP can have none, one or more bits set, and the currently defined
bits are:
.TP 5.5
.B CURL_VERSION_IPV6
supports IPv6
.TP
.B CURL_VERSION_KERBEROS4
supports kerberos4 (when using FTP)
.TP
.B CURL_VERSION_SSL
supports SSL (HTTPS/FTPS)
.TP
.B CURL_VERSION_LIBZ
supports HTTP deflate using libz
.TP
.B CURL_VERSION_NTLM
supports HTTP NTLM (added in 7.10.6)
.TP
.B CURL_VERSION_GSSNEGOTIATE
supports HTTP GSS-Negotiate (added in 7.10.6)
.TP
.B CURL_VERSION_DEBUG
libcurl was built with extra debug capabilities built-in. This is mainly of
interest for libcurl hackers. (added in 7.10.6)
.TP
.B 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)
.TP
.B 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)
.PP
\fIssl_version\fP is an ascii string for the OpenSSL version used. If libcurl
has no SSL support, this is NULL.

\fIssl_version_num\fP is the numerical OpenSSL version value as defined by the
OpenSSL project. If libcurl has no SSL support, this is 0.

\fIlibz_version\fP is an ascii string (there is no numerical version). If
libcurl has no libz support, this is NULL.

\fIprotocols\fP 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.
.SH RETURN VALUE
A pointer to a curl_version_info_data struct.
.SH "SEE ALSO"
\fIcurl_version(3)\fP