iw7-mod/deps/curl/docs/libcurl/curl_url_get.md
2024-08-13 05:15:34 -04:00

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---
c: Copyright (C) Daniel Stenberg, <daniel@haxx.se>, et al.
SPDX-License-Identifier: curl
Title: curl_url_get
Section: 3
Source: libcurl
See-also:
- CURLOPT_CURLU (3)
- curl_url (3)
- curl_url_cleanup (3)
- curl_url_dup (3)
- curl_url_set (3)
- curl_url_strerror (3)
---
# NAME
curl_url_get - extract a part from a URL
# SYNOPSIS
~~~c
#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)
# 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.
## 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 a zero-length string.
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.
# EXAMPLE
~~~c
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 7.62.0. CURLUPART_ZONEID was added in 7.65.0.
# 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.