Ubuntu Manpage: curl_url_get - extract a part from a URL

Provided by: libcurl4-doc_8.12.1-3ubuntu1_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.