curl-w32/docs/libcurl/libcurl-url.md

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---
c: Copyright (C) Daniel Stenberg, <daniel.se>, et al.
SPDX-License-Identifier: curl
Title: libcurl
Section: 3
Source: libcurl
See-also:
- CURLOPT_URL (3)
- curl_url (3)
- curl_url_cleanup (3)
- curl_url_dup (3)
- curl_url_get (3)
- curl_url_set (3)
- curl_url_strerror (3)
---
# NAME
libcurl-url - URL interface overview
# DESCRIPTION
The URL interface provides functions for parsing and generating URLs.
# INCLUDE
You still only include <curl/curl.h> in your code.
# CREATE
Create a handle that holds URL info and resources with curl_url(3):
~~~c
CURLU *h = curl_url();
~~~
# CLEANUP
When done with it, clean it up with curl_url_cleanup(3)
~~~c
curl_url_cleanup(h);
~~~
# DUPLICATE
When you need a copy of a handle, just duplicate it with curl_url_dup(3):
~~~c
CURLU *nh = curl_url_dup(h);
~~~
# PARSING
By setting a URL to the handle with curl_url_set(3), the URL is parsed
and stored in the handle. If the URL is not syntactically correct it returns
an error instead.
~~~c
rc = curl_url_set(h, CURLUPART_URL,
"https://example.com:449/foo/bar?name=moo", 0);
~~~
The zero in the fourth argument is a bitmask for changing specific features.
If successful, this stores the URL in its individual parts within the handle.
# REDIRECT
When a handle already contains info about a URL, setting a relative URL makes
it "redirect" to that.
~~~c
rc = curl_url_set(h, CURLUPART_URL, "../test?another", 0);
~~~
# GET URL
The **CURLU** handle represents a URL and you can easily extract that with
curl_url_get(3):
~~~c
char *url;
rc = curl_url_get(h, CURLUPART_URL, &url, 0);
curl_free(url);
~~~
The zero in the fourth argument is a bitmask for changing specific features.
# GET PARTS
When a URL has been parsed or parts have been set, you can extract those
pieces from the handle at any time.
~~~c
rc = curl_url_get(h, CURLUPART_FRAGMENT, &fragment, 0);
rc = curl_url_get(h, CURLUPART_HOST, &host, 0);
rc = curl_url_get(h, CURLUPART_PASSWORD, &password, 0);
rc = curl_url_get(h, CURLUPART_PATH, &path, 0);
rc = curl_url_get(h, CURLUPART_PORT, &port, 0);
rc = curl_url_get(h, CURLUPART_QUERY, &query, 0);
rc = curl_url_get(h, CURLUPART_SCHEME, &scheme, 0);
rc = curl_url_get(h, CURLUPART_USER, &user, 0);
rc = curl_url_get(h, CURLUPART_ZONEID, &zoneid, 0);
~~~
Extracted parts are not URL decoded unless the user also asks for it with the
*CURLU_URLDECODE* flag set in the fourth bitmask argument.
Remember to free the returned string with curl_free(3) when you are done
with it!
# SET PARTS
A user set individual URL parts, either after having parsed a full URL or
instead of parsing such.
~~~c
rc = curl_url_set(urlp, CURLUPART_FRAGMENT, "anchor", 0);
rc = curl_url_set(urlp, CURLUPART_HOST, "www.example.com", 0);
rc = curl_url_set(urlp, CURLUPART_PASSWORD, "doe", 0);
rc = curl_url_set(urlp, CURLUPART_PATH, "/index.html", 0);
rc = curl_url_set(urlp, CURLUPART_PORT, "443", 0);
rc = curl_url_set(urlp, CURLUPART_QUERY, "name=john", 0);
rc = curl_url_set(urlp, CURLUPART_SCHEME, "https", 0);
rc = curl_url_set(urlp, CURLUPART_USER, "john", 0);
rc = curl_url_set(urlp, CURLUPART_ZONEID, "eth0", 0);
~~~
Set parts are not URL encoded unless the user asks for it with the
*CURLU_URLENCODE* flag.
# CURLU_APPENDQUERY
An application can append a string to the right end of the query part with the
*CURLU_APPENDQUERY* flag to curl_url_set(3).
Imagine a handle that holds the URL "https://example.com/?shoes=2". An
application can then add the string "hat=1" to the query part like this:
~~~c
rc = curl_url_set(urlp, CURLUPART_QUERY, "hat=1", CURLU_APPENDQUERY);
~~~
It notices the lack of an ampersand (&) separator and injects one, and the
handle's full URL then equals "https://example.com/?shoes=2&hat=1".
The appended string can of course also get URL encoded on add, and if asked to
URL encode, the encoding process skips the '=' character. For example, append
"candy=N&N" to what we already have, and URL encode it to deal with the
ampersand in the data:
~~~c
rc = curl_url_set(urlp, CURLUPART_QUERY, "candy=N&N",
CURLU_APPENDQUERY | CURLU_URLENCODE);
~~~
Now the URL looks like
~~~c
https://example.com/?shoes=2&hat=1&candy=N%26N
~~~
# AVAILABILITY
The URL API was introduced in libcurl 7.62.0.
A URL with a literal IPv6 address can be parsed even when IPv6 support is not
enabled.