Provided by: libcurl4-doc_8.9.1-2ubuntu2.2_all bug

NAME

       CURLOPT_URL - URL for this transfer

SYNOPSIS

       #include <curl/curl.h>

       CURLcode curl_easy_setopt(CURL *handle, CURLOPT_URL, char *URL);

DESCRIPTION

       Pass  in  a pointer to the URL to work with. The parameter should be a char * to a null-terminated string
       which must be URL-encoded in the following format:

       scheme://host:port/path

       For a greater explanation of the format please see RFC 3986.

       libcurl does not validate the syntax or use the URL until the transfer is started.  Even  if  you  set  a
       crazy value here, curl_easy_setopt(3) might still return CURLE_OK.

       If  the given URL is missing a scheme name (such as "http://" or "ftp://" etc) then libcurl guesses based
       on the host. If the outermost subdomain name matches DICT, FTP,  IMAP,  LDAP,  POP3  or  SMTP  then  that
       protocol  gets  used,  otherwise HTTP is used. Since 7.45.0 guessing can be disabled by setting a default
       protocol, see CURLOPT_DEFAULT_PROTOCOL(3) for details.

       Should the protocol, either as specified by the URL scheme or deduced by libcurl from the  hostname,  not
       be  supported by libcurl then CURLE_UNSUPPORTED_PROTOCOL is returned from either the curl_easy_perform(3)
       or curl_multi_perform(3) functions when you call them. Use curl_version_info(3) for detailed  information
       of which protocols are supported by the build of libcurl you are using.

       CURLOPT_PROTOCOLS_STR(3)  can  be  used  to  limit  what  protocols  libcurl  may  use for this transfer,
       independent of what libcurl has been compiled to support. That may be useful if you accept the  URL  from
       an external source and want to limit the accessibility.

       The CURLOPT_URL(3) string is ignored if CURLOPT_CURLU(3) is set.

       Either CURLOPT_URL(3) or CURLOPT_CURLU(3) must be set before a transfer is started.

       The application does not have to keep the string around after setting this option.

       The parser used for handling the URL set with CURLOPT_URL(3) is the same that curl_url_set(3) uses.

ENCODING

       The string pointed to in the CURLOPT_URL(3) argument is generally expected to be a sequence of characters
       using an ASCII compatible encoding.

       If libcurl is built with IDN support, the server name part of the URL can use an "international name"  by
       using  the  current  encoding  (according  to locale) or UTF-8 (when winidn is used; or a Windows Unicode
       build using libidn2).

       If libcurl is built without IDN support, the server name is used exactly as specified when passed to  the
       name resolver functions.

DEFAULT

       NULL. If this option is not set, no transfer can be performed.

SECURITY CONCERNS

       Applications may at times find it convenient to allow users to specify URLs for various purposes and that
       string would then end up fed to this option.

       Getting a URL from an external untrusted party brings several security concerns:

       If you have an application that runs as or in a server application, getting an unfiltered URL can  easily
       trick  your  application  to  access  a  local  resource instead of a remote. Protecting yourself against
       localhost accesses is hard when accepting user provided URLs.

       Such custom URLs can also access other ports than you planned as port numbers are part of the regular URL
       format.  The combination of a local host and a custom port number can allow external users to play tricks
       with your local services.

       Accepting external URLs may also use other protocols than http:// or other  common  ones.  Restrict  what
       accept with CURLOPT_PROTOCOLS_STR(3).

       User  provided  URLs  can  also  be  made  to  point to sites that redirect further on (possibly to other
       protocols too). Consider your CURLOPT_FOLLOWLOCATION(3) and CURLOPT_REDIR_PROTOCOLS_STR(3) settings.

PROTOCOLS

       This functionality affects all supported protocols

EXAMPLE

       int main(void)
       {
         CURL *curl = curl_easy_init();
         if(curl) {
           curl_easy_setopt(curl, CURLOPT_URL, "https://example.com");

           curl_easy_perform(curl);
         }
       }

AVAILABILITY

       Added in curl 7.1

RETURN VALUE

       Returns CURLE_OK on success or CURLE_OUT_OF_MEMORY if there was insufficient heap space.

       Note that curl_easy_setopt(3) does not parse the given string so given a bad  URL,  it  is  not  detected
       until curl_easy_perform(3) or similar is called.

SEE ALSO

       CURLINFO_REDIRECT_URL(3),     CURLOPT_CURLU(3),     CURLOPT_FORBID_REUSE(3),    CURLOPT_FRESH_CONNECT(3),
       CURLOPT_PATH_AS_IS(3), CURLOPT_PROTOCOLS_STR(3), curl_easy_perform(3), curl_url_get(3), curl_url_set(3)