Ubuntu Manpage: curl_url_get - extract a part from a URL

Provided by: libcurl4-doc_8.9.1-2ubuntu2_all

NAME

       curl_url_get - extract a part from a URL

SYNOPSIS

       #include <curl/curl.h>

       CURLUcode curl_url_get(const CURLU *url,
                              CURLUPart part,
                              char **content,
                              unsigned int flags);

DESCRIPTION

       Given a url handle of a URL object, this function extracts an individual piece or the full
       URL from it.

       The part argument specifies which part to extract (see list below) and content points to a
       'char *' to get updated to point to a newly allocated string with the contents.

       The flags argument is a bitmask with individual features.

       The returned content pointer must be freed with curl_free(3) after use.

FLAGS

       The flags argument is zero, one or more bits set in a bitmask.

       CURLU_DEFAULT_PORT
              If  the  handle  has  no  port stored, this option makes curl_url_get(3) return the
              default port for the used scheme.

       CURLU_DEFAULT_SCHEME
              If the handle has no scheme stored, this option makes  curl_url_get(3)  return  the
              default scheme instead of error.

       CURLU_NO_DEFAULT_PORT
              Instructs  curl_url_get(3)  to  not  return a port number if it matches the default
              port for the scheme.

       CURLU_URLDECODE
              Asks curl_url_get(3) to URL decode the contents before returning it.  It  does  not
              decode the scheme, the port number or the full URL.

              The  query component also gets plus-to-space conversion as a bonus when this bit is
              set.

              Note that this URL decoding is charset unaware and you get a zero terminated string
              back with data that could be intended for a particular encoding.

              If  there  are  byte  values lower than 32 in the decoded string, the get operation
              returns an error instead.

       CURLU_URLENCODE
              If set, curl_url_get(3) URL encodes the hostname part when a full URL is retrieved.
              If  not set (default), libcurl returns the URL with the hostname raw to support IDN
              names to appear as-is. IDN hostnames  are  typically  using  non-ASCII  bytes  that
              otherwise gets percent-encoded.

              Note  that  even when not asking for URL encoding, the '%' (byte 37) is URL encoded
              to make sure the hostname remains valid.

       CURLU_PUNYCODE
              If set and CURLU_URLENCODE is not set, and asked to retrieve the CURLUPART_HOST  or
              CURLUPART_URL  parts,  libcurl  returns the host name in its punycode version if it
              contains any non-ASCII octets (and is an IDN name).

              If libcurl is built without IDN capabilities, using this bit makes  curl_url_get(3)
              return CURLUE_LACKS_IDN if the hostname contains anything outside the ASCII range.

              (Added in curl 7.88.0)

       CURLU_PUNY2IDN
              If  set  and  asked  to retrieve the CURLUPART_HOST or CURLUPART_URL parts, libcurl
              returns the hostname in its IDN (International Domain Name)  UTF-8  version  if  it
              otherwise  is  a  punycode version. If the punycode name cannot be converted to IDN
              correctly, libcurl returns CURLUE_BAD_HOSTNAME.

              If libcurl is built without IDN capabilities, using this bit makes  curl_url_get(3)
              return CURLUE_LACKS_IDN if the hostname is using punycode.

              (Added in curl 8.3.0)

       CURLU_GET_EMPTY
              When  this flag is used in curl_url_get(), it makes the function return empty query
              and fragments parts or when used in the full URL.  By  default,  libcurl  otherwise
              considers empty parts non-existing.

              An  empty  query  part  is  one  where  this is nothing following the question mark
              (before the possible fragment). An empty fragments  part  is  one  where  there  is
              nothing following the hash sign.

              (Added in curl 8.8.0)

       CURLU_NO_GUESS_SCHEME
              When  this  flag is used in curl_url_get(), it treats the scheme as non-existing if
              it was set as a result of  a  previous  guess;  when  CURLU_GUESS_SCHEME  was  used
              parsing a URL.

              Using  this  flag when getting CURLUPART_SCHEME if the scheme was set as the result
              of a guess makes curl_url_get() return CURLUE_NO_SCHEME.

              Using this flag when getting CURLUPART_URL if the scheme was set as the result of a
              guess makes curl_url_get() return the full URL without the scheme component. Such a
              URL can then only be parsed with curl_url_set() if CURLU_GUESS_SCHEME is used.

              (Added in curl 8.9.0)

PARTS

CURLUPART_URL
When asked to return the full URL, curl_url_get(3) returns a normalized and
possibly cleaned up version using all available URL parts.

We advise using the CURLU_PUNYCODE option to get the URL as "normalized" as
possible since IDN allows hostnames to be written in many different ways that still
end up the same punycode version.

Zero-length queries and fragments are excluded from the URL unless CURLU_GET_EMPTY
is set.

CURLUPART_SCHEME
Scheme cannot be URL decoded on get.

CURLUPART_USER

CURLUPART_PASSWORD

CURLUPART_OPTIONS
The options field is an optional field that might follow the password in the
userinfo part. It is only recognized/used when parsing URLs for the following
schemes: pop3, smtp and imap. The URL API still allows users to set and get this
field independently of scheme when not parsing full URLs.

CURLUPART_HOST
The hostname. If it is an IPv6 numeric address, the zone id is not part of it but
is provided separately in CURLUPART_ZONEID. IPv6 numerical addresses are returned
within brackets ([]).

IPv6 names are normalized when set, which should make them as short as possible
while maintaining correct syntax.

CURLUPART_ZONEID
If the hostname is a numeric IPv6 address, this field might also be set.

CURLUPART_PORT
A port cannot be URL decoded on get. This number is returned in a string just like
all other parts. That string is guaranteed to hold a valid port number in ASCII
using base 10.

CURLUPART_PATH
The part is always at least a slash ('/') even if no path was supplied in the URL.
A URL path always starts with a slash.

CURLUPART_QUERY
The initial question mark that denotes the beginning of the query part is a
delimiter only. It is not part of the query contents.

A not-present query returns part set to NULL.

A zero-length query returns part as NULL unless CURLU_GET_EMPTY is set.

The query part gets pluses converted to space when asked to URL decode on get with
the CURLU_URLDECODE bit.

CURLUPART_FRAGMENT
The initial hash sign that denotes the beginning of the fragment is a delimiter
only. It is not part of the fragment contents.

A not-present fragment returns part set to NULL.

A zero-length fragment returns part as NULL unless CURLU_GET_EMPTY is set.

PROTOCOLS

       This functionality affects all supported protocols

EXAMPLE

       int main(void)
       {
         CURLUcode rc;
         CURLU *url = curl_url();
         rc = curl_url_set(url, CURLUPART_URL, "https://example.com", 0);
         if(!rc) {
           char *scheme;
           rc = curl_url_get(url, CURLUPART_SCHEME, &scheme, 0);
           if(!rc) {
             printf("the scheme is %s\n", scheme);
             curl_free(scheme);
           }
           curl_url_cleanup(url);
         }
       }

AVAILABILITY

       Added in curl 7.62.0

RETURN VALUE

       Returns a CURLUcode error value, which is CURLUE_OK (0) if everything went fine.  See  the
       libcurl-errors(3) man page for the full list with descriptions.

       If this function returns an error, no URL part is returned.