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NativeSPTransportOption

The <TransportOption> element allows implementation-specific properties to be passed into the SOAP transport implementation class, bypassing the usual abstractions.

This can be a powerful, but dangerous feature. Used improperly, crashes are quite possible to induce.

<TransportOption provider="CURL" option="100">2</TransportOption>

General Attributes

  • provider(string)
    • Identifies the transport implementation the option is intended to be passed into. "CURL" is generally supported, and "OpenSSL" is supported in Version 2.4 and higher.

CURL Provider

When provider is set to "CURL", the following information applies.

Attributes

  • option(string)
    • A CURL option number, which can be determined by examining the curl.h header file or the curl_easy_init man page. Find below a list of options:

       Show extract from curl_easy_init manpage
      [...]
      
      NETWORK OPTIONS
             CURLOPT_URL (10002)
                The actual URL to deal with. The parameter should be a char * to
                a zero terminated string.
      
                If  the given URL lacks the protocol part ("http://" or "ftp://"
                etc), it will attempt to guess which protocol to  use  based  on
                the given host name. If the given protocol of the set URL is not
                supported, libcurl will return on error  (CURLE_UNSUPPORTED_PRO-
                TOCOL)  when  you  call  curl_easy_perform(3) or curl_multi_per-
                form(3). Use curl_version_info(3) for  detailed  info  on  which
                protocols are supported.
      
                The  string  given to CURLOPT_URL (10002) must be url-encoded and follow
                RFC 2396 (http://curl.haxx.se/rfc/rfc2396.txt).
      
                Starting with version 7.20.0, the fragment part of the URI  will
                not  be send as part of the path, which was the case previously.
      
                CURLOPT_URL (10002)  is  the  only  option  that  must  be  set   before
                curl_easy_perform(3) is called.
      
                CURLOPT_PROTOCOLS (181)  can  be  used to limit what protocols libcurl
                will 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.
      
             CURLOPT_PROTOCOLS (181)
                Pass a long that holds a  bitmask  of  CURLPROTO_*  defines.  If
                used,  this bitmask limits what protocols libcurl may use in the
                transfer. This allows you to have a libcurl built to  support  a
                wide  range  of  protocols but still limit specific transfers to
                only be allowed to use a subset of them. By default libcurl will
                accept  all protocols it supports. See also CURLOPT_REDIR_PROTO-
                COLS. (Added in 7.19.4)
      
             CURLOPT_REDIR_PROTOCOLS (182)
                Pass a long that holds a  bitmask  of  CURLPROTO_*  defines.  If
                used,  this  bitmask  limits what protocols libcurl may use in a
                transfer that it follows to in a redirect when CURLOPT_FOLLOWLO-
                CATION  is  enabled. This allows you to limit specific transfers
                to only be allowed to use a subset of protocols in redirections.
                By  default libcurl will allow all protocols except for FILE and
                SCP. This is a difference compared to pre-7.19.4 versions  which
                unconditionally  would follow to all protocols supported. (Added
                in 7.19.4)
      
             CURLOPT_PROXY (10004)
                Set HTTP proxy to use. The parameter should be a  char  *  to  a
                zero  terminated  string  holding  the  host  name  or dotted IP
                address. To specify port number in this string,  append  :[port]
                to  the  end  of the host name. The proxy string may be prefixed
                with [protocol]:// since any such prefix will  be  ignored.  The
                proxy's  port  number may optionally be specified with the sepa-
                rate option. If not specified, libcurl  will  default  to  using
                port 1080 for proxies.  CURLOPT_PROXY (10004)PORT.
      
                When  you  tell  the  library to use an HTTP proxy, libcurl will
                transparently convert operations to HTTP even if you specify  an
                FTP  URL  etc. This may have an impact on what other features of
                the library you can use, such as CURLOPT_QUOTE (10028) and  similar  FTP
                specifics  that  don't  work  unless you tunnel through the HTTP
                proxy. Such tunneling is activated with CURLOPT_HTTPPROXYTUNNEL (61).
      
                libcurl   respects   the   environment   variables   http_proxy,
                ftp_proxy, all_proxy etc, if any of  those  are  set.  The  CUR-
                LOPT_PROXY  option  does however override any possibly set envi-
                ronment variables.
      
                Setting the proxy string to "" (an empty string) will explicitly
                disable  the  use  of  a  proxy, even if there is an environment
                variable set for it.
      
                Since 7.14.1, the proxy host string given in  environment  vari-
                ables  can  be  specified the exact same way as the proxy can be
                set with CURLOPT_PROXY (10004), include protocol  prefix  (http://)  and
                embedded user + password.
      
             CURLOPT_PROXYPORT (10004)
                Pass a long with this option to set the proxy port to connect to
                unless it is specified in the proxy string CURLOPT_PROXY (10004).
      
             CURLOPT_PROXYTYPE (10004)
                Pass a long with this option to set type of the proxy. Available
                options  for  this are CURLPROXY_HTTP, CURLPROXY_HTTP_1_0 (added
                in  7.19.4),   CURLPROXY_SOCKS4   (4),   CURL-
                PROXY_SOCKS5,  CURLPROXY_SOCKS4A  (6)  and CURL-
                PROXY_SOCKS5_HOSTNAME  (7).  The  HTTP  type  is
                default. (Added in 7.10)
      
             CURLOPT_NOPROXY (10177)
                Pass  a  pointer  to  a  zero terminated string. The should be a
                comma- separated list of hosts which do not use a proxy, if  one
                is  specified.  The only wildcard is a single * character, which
                matches all hosts, and effectively disables the proxy. Each name
                in  this  list  is matched as either a domain which contains the
                hostname, or the hostname itself. For example,  local.com  would
                match   local.com,  local.com:80,  and  www.local.com,  but  not
                www.notlocal.com.  (Added in 7.19.4)
      
             CURLOPT_HTTPPROXYTUNNEL (61)
                Set the parameter to 1 to make the library tunnel all operations
                through  a  given  HTTP proxy. There is a big difference between
                using a proxy and to tunnel through it. If you don't  know  what
                this means, you probably don't want this tunneling option.
      
             CURLOPT_SOCKS5_GSSAPI_SERVICE (10179)
                Pass  a  char * as parameter to a string holding the name of the
                service. The  default  service  name  for  a  SOCKS5  server  is
                rcmd/server-fqdn. This option allows you to change it. (Added in
                7.19.4)
      
             CURLOPT_SOCKS5_GSSAPI_NEC (180)
                Pass a long set to 1 to enable or 0 to disable. As part  of  the
                gssapi  negotiation a protection mode is negotiated. The rfc1961
                says in section 4.3/4.4 it should be protected, but the NEC ref-
                erence  implementation does not.  If enabled, this option allows
                the unprotected exchange of  the  protection  mode  negotiation.
                (Added in 7.19.4).
      
             CURLOPT_INTERFACE (10062)
                Pass  a char * as parameter. This sets the interface name to use
                as outgoing network interface. The  name  can  be  an  interface
                name, an IP address, or a host name.
      
             CURLOPT_LOCALPORT (139)
                Pass  a long. This sets the local port number of the socket used
                for connection. This  can  be  used  in  combination  with  CUR-
                LOPT_INTERFACE  and you are recommended to use CURLOPT_LOCALPOR-
                TRANGE as well when this is set. Valid  port  numbers  are  1  -
                65535. (Added in 7.15.2)
      
             CURLOPT_LOCALPORT (139)RANGE
                Pass  a long. This is the number of attempts libcurl should make
                to find a working local port number. It starts  with  the  given
                CURLOPT_LOCALPORT (139)  and  adds  one  to the number for each retry.
                Setting this to 1 or below will make libcurl do only one try for
                the  exact  port  number.  Port  numbers  by  nature  are scarce
                resources that will be busy at times so setting  this  value  to
                something too low might cause unnecessary connection setup fail-
                ures. (Added in 7.15.2)
      
             CURLOPT_DNS_CACHE_TIMEOUT (92)
                Pass a long, this sets the timeout  in  seconds.  Name  resolves
                will  be  kept in memory for this number of seconds. Set to zero
                to completely disable caching, or set to -1 to make  the  cached
                entries remain forever. By default, libcurl caches this info for
                60 seconds.
      
                The name resolve functions of various libc implementations don't
                re-read  name  server information unless explicitly told so (for
                example, by calling res_init(3)). This may cause libcurl to keep
                using the older server even if DHCP has updated the server info,
                and this may look like a DNS cache issue to the casual  libcurl-
                app user.
      
             CURLOPT_DNS_USE_GLOBAL_CACHE (91)
                Pass  a  long.  If the value is 1, it tells curl to use a global
                DNS cache that will survive between easy  handle  creations  and
                deletions.  This  is  not thread-safe and this will use a global
                variable.
      
                WARNING: this option is  considered  obsolete.  Stop  using  it.
                Switch  over  to  using  the  share  interface instead! See CUR-
                LOPT_SHARE and curl_share_init.
      
             CURLOPT_BUFFERSIZE (98)
                Pass a long specifying your preferred size (in  bytes)  for  the
                receive buffer in libcurl.  The main point of this would be that
                the write callback gets  called  more  often  and  with  smaller
                chunks.  This  is  just  treated as a request, not an order. You
                cannot be guaranteed to actually get the given size.  (Added  in
                7.10)
      
                This   size   is   by   default   set   as   big   as   possible
                (CURL_MAX_WRITE_SIZE), so it only makes sense to use this option
                if you want it smaller.
      
             CURLOPT_PORT (3)
                Pass  a  long  specifying what remote port number to connect to,
                instead of the one specified in the URL or the default port  for
                the used protocol.
      
             CURLOPT_TCP_NODELAY (121)
                Pass  a long specifying whether the TCP_NODELAY option should be
                set or cleared (1 = set, 0 = clear). The option  is  cleared  by
                default.  This will have no effect after the connection has been
                established.
      
                Setting this option will disable TCP's Nagle algorithm. The pur-
                pose of this algorithm is to try to minimize the number of small
                packets on the network (where "small packets" means TCP segments
                less than the Maximum Segment Size (MSS) for the network).
      
                Maximizing  the  amount  of  data  sent  per TCP segment is good
                because it amortizes the overhead of the send. However, in  some
                cases (most notably telnet or rlogin) small segments may need to
                be sent without delay.  This  is  less  efficient  than  sending
                larger  amounts of data at a time, and can contribute to conges-
                tion on the network if overdone.
      
             CURLOPT_ADDRESS_SCOPE (171)
                Pass a long specifying the scope_id value to use when connecting
                to IPv6 link-local or site-local addresses. (Added in 7.19.0)
      
      NAMES and PASSWORDS OPTIONS (Authentication)
             CURLOPT_NETRC (51)
                This  parameter controls the preference of libcurl between using
                user names and passwords from your ~/.netrc  file,  relative  to
                user names and passwords in the URL supplied with CURLOPT_URL (10002).
      
                libcurl  uses  a  user  name (and supplied or prompted password)
                supplied with  CURLOPT_USERPWD (10005)  in  preference  to  any  of  the
                options controlled by this parameter.
      
                Pass a long, set to one of the values described below.
      
                CURL_NETRC_OPTIONAL
                   The  use  of your ~/.netrc file is optional, and informa-
                   tion in the URL is to be preferred.   The  file  will  be
                   scanned  for the host and user name (to find the password
                   only) or for the host only, to find the first  user  name
                   and  password  after that machine, which ever information
                   is not specified in the URL.
      
                   Undefined values of the option will have this effect.
      
                CURL_NETRC_IGNORED
                   The library will ignore the file and use only the  infor-
                   mation in the URL.
      
                   This is the default.
      
                CURL_NETRC_REQUIRED
                   This  value  tells  the  library  that use of the file is
                   required, to ignore the information in the  URL,  and  to
                   search the file for the host only.
             Only  machine name, user name and password are taken into account (init
             macros and similar things aren't supported).
      
             libcurl does not verify that the file has the  correct  properties  set
             (as  the  standard Unix ftp client does). It should only be readable by
             user.
      
             CURLOPT_NETRC_FILE (51)
                Pass a char * as parameter, pointing to a zero terminated string
                containing  the  full  path name to the file you want libcurl to
                use as .netrc file. If this option is omitted, and CURLOPT_NETRC (51)
                is  set,  libcurl will attempt to find a .netrc file in the cur-
                rent user's home directory. (Added in 7.10.9)
      
             CURLOPT_USERPWD (10005)
                Pass a char * as parameter, which should be  [user  name]:[pass-
                word]  to use for the connection. Use CURLOPT_HTTPAUTH (107) to decide
                the authentication method.
      
                When using NTLM, you can set the domain by prepending it to  the
                user  name and separating the domain and name with a forward (/)
                or backward slash  (\).  Like  this:  "domain/user:password"  or
                "domain\user:password".  Some  HTTP servers (on Windows) support
                this style even for Basic authentication.
      
                When using HTTP and CURLOPT_FOLLOWLOCATION (52), libcurl  might  per-
                form  several requests to possibly different hosts. libcurl will
                only send this user and password information to hosts using  the
                initial  host name (unless CURLOPT_UNRESTRICTED_AUTH (105) is set), so
                if libcurl follows locations to other hosts it will not send the
                user and password to those. This is enforced to prevent acciden-
                tal information leakage.
      
             CURLOPT_PROXY (10004)USERPWD
                Pass a char * as parameter, which should be  [user  name]:[pass-
                word]  to  use  for  the connection to the HTTP proxy.  Use CUR-
                LOPT_PROXYAUTH to decide the authentication method.
      
             CURLOPT_USERNAME (10173)
                Pass a char * as parameter, which should be pointing to the zero
                terminated user name to use for the transfer.
      
                CURLOPT_USERNAME (10173)  sets  the  user  name  to  be used in protocol
                authentication. You should not use this option together with the
                (older) CURLOPT_USERPWD (10005) option.
      
                In  order to specify the password to be used in conjunction with
                the user  name  use  the  CURLOPT_PASSWORD (10174)  option.   (Added  in
                7.19.1)
      
             CURLOPT_PASSWORD (10174)
                Pass a char * as parameter, which should be pointing to the zero
                terminated password to use for the transfer.
      
                The CURLOPT_PASSWORD (10174) option should be used in  conjunction  with
                the CURLOPT_USERNAME (10173) option. (Added in 7.19.1)
      
             CURLOPT_PROXY (10004)USERNAME
                Pass a char * as parameter, which should be pointing to the zero
                terminated user name to use for the transfer while connecting to
                Proxy.
      
                The  CURLOPT_PROXY (10004)USERNAME  option should be used in same way as
                the  CURLOPT_PROXY (10004)USERPWD  is  used.   In  comparison  to   CUR-
                LOPT_PROXYUSERPWD  the CURLOPT_PROXY (10004)USERNAME allows the username
                to  contain  a   colon,   like   in   the   following   example:
                "sip:user@example.com".  The  CURLOPT_PROXY (10004)USERNAME option is an
                alternative way to set the user name while connecting to  Proxy.
                There  is  no  meaning to use it together with the CURLOPT_PROX-
                YUSERPWD option.
      
                In order to specify the password to be used in conjunction  with
                the  user  name use the CURLOPT_PROXY (10004)PASSWORD option.  (Added in
                7.19.1)
      
             CURLOPT_PROXY (10004)PASSWORD
                Pass a char * as parameter, which should be pointing to the zero
                terminated  password to use for the transfer while connecting to
                Proxy.
      
                The CURLOPT_PROXY (10004)PASSWORD option should be used  in  conjunction
                with the CURLOPT_PROXY (10004)USERNAME option. (Added in 7.19.1)
      
             CURLOPT_HTTPAUTH (107)
                Pass  a  long  as  parameter, which is set to a bitmask, to tell
                libcurl which authentication method(s) you want it to  use.  The
                available  bits  are  listed below. If more than one bit is set,
                libcurl will first query the site to  see  which  authentication
                methods  it  supports and then pick the best one you allow it to
                use. For some methods, this will induce an extra network  round-
                trip.  Set the actual name and password with the CURLOPT_USERPWD (10005)
                option or with the CURLOPT_USERNAME (10173) and the CURLOPT_USERPASSWORD
                options.  (Added in 7.10.6)
      
                CURLAUTH_BASIC
                   HTTP  Basic  authentication.  This is the default choice,
                   and the only method that is in wide-spread use  and  sup-
                   ported virtually everywhere. This sends the user name and
                   password over the network in plain text, easily  captured
                   by others.
      
                CURLAUTH_DIGEST
                   HTTP  Digest  authentication.   Digest  authentication is
                   defined in RFC2617 and is a more secure way to do authen-
                   tication  over public networks than the regular old-fash-
                   ioned Basic method.
      
                CURLAUTH_DIGEST_IE
                   HTTP Digest authentication with  an  IE  flavor.   Digest
                   authentication is defined in RFC2617 and is a more secure
                   way to do authentication over public  networks  than  the
                   regular old-fashioned Basic method. The IE flavor is sim-
                   ply that libcurl will use a special "quirk"  that  IE  is
                   known to have used before version 7 and that some servers
                   require the client to use.  (This  define  was  added  in
                   7.19.3)
      
                CURLAUTH_GSSNEGOTIATE
                   HTTP   GSS-Negotiate  authentication.  The  GSS-Negotiate
                   (also known as plain "Negotiate") method was designed  by
                   Microsoft  and  is  used in their web applications. It is
                   primarily meant as a support for Kerberos5 authentication
                   but  may  also  be  used  along with other authentication
                   methods. For  more  information  see  IETF  draft  draft-
                   brezak-spnego-http-04.txt.
      
                   You need to build libcurl with a suitable GSS-API library
                   for this to work.
      
                CURLAUTH_NTLM
                   HTTP NTLM authentication. A proprietary protocol invented
                   and  used  by Microsoft. It uses a challenge-response and
                   hash concept similar to Digest, to prevent  the  password
                   from being eavesdropped.
      
                   You  need  to build libcurl with OpenSSL support for this
                   option to work, or build libcurl on Windows.
      
                CURLAUTH_ANY
                   This is a convenience macro that sets all bits  and  thus
                   makes  libcurl  pick  any it finds suitable. libcurl will
                   automatically select the one it finds most secure.
      
                CURLAUTH_ANYSAFE
                   This is a convenience macro that  sets  all  bits  except
                   Basic  and thus makes libcurl pick any it finds suitable.
                   libcurl will automatically select the one it  finds  most
                   secure.
      
             CURLOPT_PROXY (10004)AUTH
                Pass  a  long  as  parameter, which is set to a bitmask, to tell
                libcurl which authentication method(s) you want it  to  use  for
                your proxy authentication.  If more than one bit is set, libcurl
                will first query the site to see what authentication methods  it
                supports  and  then  pick  the best one you allow it to use. For
                some methods, this will induce an extra network round-trip.  Set
                the  actual  name  and  password  with  the CURLOPT_PROXY (10004)USERPWD
                option. The bitmask can be constructed by  or'ing  together  the
                bits  listed  above  for the CURLOPT_HTTPAUTH (107) option. As of this
                writing, only Basic, Digest and NTLM work. (Added in 7.10.7)
      
      HTTP OPTIONS
             CURLOPT_AUTOREFERER (58)
                Pass a parameter set to 1 to enable this. When enabled,  libcurl
                will  automatically  set the Referer: field in requests where it
                follows a Location: redirect.
      
             CURLOPT_ENCODING (10102)
                Sets the contents of the Accept-Encoding: header sent in an HTTP
                request,  and  enables  decoding  of  a response when a Content-
                Encoding: header is received.  Three  encodings  are  supported:
                identity,  which does nothing, deflate which requests the server
                to compress its response using  the  zlib  algorithm,  and  gzip
                which  requests  the gzip algorithm.  If a zero-length string is
                set, then an Accept-Encoding: header  containing  all  supported
                encodings is sent.
      
                This  is  a  request, not an order; the server may or may not do
                it.  This option must be set (to any non-NULL value) or else any
                unsolicited encoding done by the server is ignored. See the spe-
                cial file lib/README.encoding for details.
      
             CURLOPT_FOLLOWLOCATION (52)
                A parameter set to 1 tells the library to follow  any  Location:
                header that the server sends as part of an HTTP header.
      
                This means that the library will re-send the same request on the
                new location and follow new Location: headers all the way  until
                no more such headers are returned. CURLOPT_MAXREDIRS (68) can be used
                to limit the number of redirects libcurl will follow.
      
                Since 7.19.4, libcurl can limit what protocols it will automati-
                cally   follow.   The  accepted  protocols  are  set  with  CUR-
                LOPT_REDIR_PROTOCOLS  and  it  excludes  the  FILE  protocol  by
                default.
      
             CURLOPT_UNRESTRICTED_AUTH (105)
                A  parameter  set to 1 tells the library it can continue to send
                authentication (user+password) when  following  locations,  even
                when  hostname changed. This option is meaningful only when set-
                ting CURLOPT_FOLLOWLOCATION (52).
      
             CURLOPT_MAXREDIRS (68)
                Pass a long. The set number will be the  redirection  limit.  If
                that  many  redirections  have  been followed, the next redirect
                will cause an error (CURLE_TOO_MANY_REDIRECTS). This option only
                makes  sense  if  the CURLOPT_FOLLOWLOCATION (52) is used at the same
                time. Added in 7.15.1: Setting the limit to 0 will make  libcurl
                refuse  any  redirect.  Set  it  to -1 for an infinite number of
                redirects (which is the default)
      
             CURLOPT_POST (47)REDIR
                Pass a bitmask to control how libcurl acts  on  redirects  after
                POSTs that get a 301 or 302 response back.  A parameter with bit
                0 set (value CURL_REDIR_POST_301) tells the library  to  respect
                RFC  2616/10.3.2 and not convert POST requests into GET requests
                when  following  a  301  redirection.  Setting  bit   1   (value
                CURL_REDIR_POST_302)  makes  libcurl maintain the request method
                after a  302  redirect.  CURL_REDIR_POST_ALL  is  a  convenience
                define that sets both bits.
      
                The  non-RFC  behaviour  is  ubiquitous  in web browsers, so the
                library does the conversion by default to maintain  consistency.
                However, a server may require a POST to remain a POST after such
                a redirection. This option is meaningful only when setting  CUR-
                LOPT_FOLLOWLOCATION.   (Added  in 7.17.1) (This option was known
                as CURLOPT_POST (47)301 up to 7.19.0 as it only supported the 301 way
                before then)
      
             CURLOPT_PUT (54)
                A parameter set to 1 tells the library to use HTTP PUT to trans-
                fer data. The data should be set with CURLOPT_READDATA (10009) and  CUR-
                LOPT_INFILESIZE.
      
                This  option  is deprecated and starting with version 7.12.1 you
                should instead use CURLOPT_UPLOAD (46).
      
             CURLOPT_POST (47)
                A parameter set to 1 tells the library  to  do  a  regular  HTTP
                post.  This  will  also  make  the  library use a "Content-Type:
                application/x-www-form-urlencoded" header. (This is by  far  the
                most commonly used POST method).
      
                Use  one of CURLOPT_POST (47)FIELDS (10015) or CURLOPT_COPYPOSTFIELDS (10165) options
                to specify what data to post and CURLOPT_POST (47)FIELDS (10015)IZE  or  CUR-
                LOPT_POSTFIELDSIZE_LARGE to set the data size.
      
                Optionally, you can provide data to POST using the CURLOPT_READ-
                FUNCTION and CURLOPT_READDATA (10009) options but  then  you  must  make
                sure  to  not  set CURLOPT_POST (47)FIELDS (10015) to anything but NULL. When
                providing data with a callback, you must transmit it using chun-
                ked  transfer-encoding or you must set the size of the data with
                the CURLOPT_POST (47)FIELDS (10015)IZE or CURLOPT_POST (47)FIELDS (10015)IZE_LARGE option.
                To  enable  chunked encoding, you simply pass in the appropriate
                Transfer-Encoding header, see the post-callback.c example.
      
                You can override the default POST Content-Type: header  by  set-
                ting your own with CURLOPT_HTTPHEADER (10023).
      
                Using  POST with HTTP 1.1 implies the use of a "Expect: 100-con-
                tinue" header.  You can disable this header  with  CURLOPT_HTTP-
                HEADER as usual.
      
                If  you use POST to a HTTP 1.1 server, you can send data without
                knowing the size before starting the POST  if  you  use  chunked
                encoding.  You  enable  this  by adding a header like "Transfer-
                Encoding: chunked" with CURLOPT_HTTPHEADER (10023).  With  HTTP  1.0  or
                without  chunked  transfer,  you  must  specify  the size in the
                request.
      
                When setting CURLOPT_POST (47) to 1, it will automatically  set  CUR-
                LOPT_NOBODY to 0 (since 7.14.1).
      
                If  you issue a POST request and then want to make a HEAD or GET
                using the same re-used handle, you must explicitly set  the  new
                request type using CURLOPT_NOBODY (44) or CURLOPT_HTTPGET (80) or similar.
      
             CURLOPT_POST (47)FIELDS (10015)
                Pass a void * as parameter, which should be  the  full  data  to
                post in an HTTP POST operation. You must make sure that the data
                is formatted the way you want the server to receive it.  libcurl
                will  not  convert  or  encode it for you. Most web servers will
                assume this data to be url-encoded.
      
                The pointed data are NOT copied by  the  library:  as  a  conse-
                quence,  they must be preserved by the calling application until
                the transfer finishes.
      
                This POST is  a  normal  application/x-www-form-urlencoded  kind
                (and  libcurl  will  set  that Content-Type by default when this
                option is used), which is the most commonly  used  one  by  HTML
                forms.  See  also  the  CURLOPT_POST (47).  Using  CURLOPT_POST (47)FIELDS (10015)
                implies CURLOPT_POST (47).
      
                If you want to do  a  zero-byte  POST,  you  need  to  set  CUR-
                LOPT_POSTFIELDSIZE  explicitly  to  zero, as simply setting CUR-
                LOPT_POSTFIELDS to NULL or  ""  just  effectively  disables  the
                sending  of  the  specified  string. libcurl will instead assume
                that you'll send the POST data using the read callback!
      
                Using POST with HTTP 1.1 implies the use of a "Expect:  100-con-
                tinue"  header.   You can disable this header with CURLOPT_HTTP-
                HEADER as usual.
      
                To make multipart/formdata posts (aka RFC2388-posts), check  out
                the CURLOPT_HTTPPOST (10024) option.
      
             CURLOPT_POST (47)FIELDS (10015)IZE
                If  you  want to post data to the server without letting libcurl
                do a strlen() to measure the data  size,  this  option  must  be
                used.  When  this option is used you can post fully binary data,
                which otherwise is likely to fail. If this size is  set  to  -1,
                the library will use strlen() to get the size.
      
             CURLOPT_POST (47)FIELDS (10015)IZE_LARGE
                Pass  a curl_off_t as parameter. Use this to set the size of the
                CURLOPT_POST (47)FIELDS (10015) data to prevent libcurl from  doing  strlen()
                on  the data to figure out the size. This is the large file ver-
                sion of the CURLOPT_POST (47)FIELDS (10015)IZE option. (Added in 7.11.1)
      
             CURLOPT_COPYPOSTFIELDS (10165)
                Pass a char * as parameter, which should be  the  full  data  to
                post  in an HTTP POST operation. It behaves as the CURLOPT_POST (47)-
                FIELDS option, but the original data are copied by the  library,
                allowing  the  application  to overwrite the original data after
                setting this option.
      
                Because data are copied, care must  be  taken  when  using  this
                option   in   conjunction  with  CURLOPT_POST (47)FIELDS (10015)IZE  or  CUR-
                LOPT_POSTFIELDSIZE_LARGE: If the size has not been set prior  to
                CURLOPT_COPYPOSTFIELDS (10165),  the data are assumed to be a NUL-termi-
                nated string; else the stored size informs the library about the
                data  byte  count  to  copy.  In  any case, the size must not be
                changed  after  CURLOPT_COPYPOSTFIELDS (10165),  unless   another   CUR-
                LOPT_POSTFIELDS  or  CURLOPT_COPYPOSTFIELDS (10165)  option  is  issued.
                (Added in 7.17.1)
      
             CURLOPT_HTTPPOST (10024)
                Tells libcurl you want a multipart/formdata HTTP POST to be made
                and  you  instruct  what  data to pass on to the server.  Pass a
                pointer to a linked list of curl_httppost structs as  parameter.
                The easiest way to create such a list, is to use curl_formadd(3)
                as documented. The data in this list must  remain  intact  until
                you close this curl handle again with curl_easy_cleanup(3).
      
                Using  POST with HTTP 1.1 implies the use of a "Expect: 100-con-
                tinue" header.  You can disable this header  with  CURLOPT_HTTP-
                HEADER as usual.
      
                When  setting  CURLOPT_HTTPPOST (10024),  it will automatically set CUR-
                LOPT_NOBODY to 0 (since 7.14.1).
      
             CURLOPT_REFERER (10016)
                Pass a pointer to a zero terminated string as parameter. It will
                be  used  to set the Referer: header in the http request sent to
                the remote server. This can be used to fool servers or  scripts.
                You can also set any custom header with CURLOPT_HTTPHEADER (10023).
      
             CURLOPT_USERAGENT (10018)
                Pass a pointer to a zero terminated string as parameter. It will
                be used to set the User-Agent: header in the http  request  sent
                to  the  remote  server.  This  can  be  used to fool servers or
                scripts. You can also set any custom header  with  CURLOPT_HTTP-
                HEADER.
      
             CURLOPT_HTTPHEADER (10023)
                Pass  a  pointer to a linked list of HTTP headers to pass to the
                server in your HTTP request. The linked list should be  a  fully
                valid  list of struct curl_slist structs properly filled in. Use
                curl_slist_append(3)     to     create     the     list      and
                curl_slist_free_all(3)  to clean up an entire list. If you add a
                header that is otherwise generated and used  by  libcurl  inter-
                nally,  your added one will be used instead. If you add a header
                with no content as in 'Accept:' (no data on the  right  side  of
                the  colon), the internally used header will get disabled. Thus,
                using this option you can  add  new  headers,  replace  internal
                headers  and  remove  internal  headers. To add a header with no
                content, make  the  content  be  two  quotes:  "".  The  headers
                included in the linked list must not be CRLF-terminated, because
                curl adds CRLF after each header item. Failure  to  comply  with
                this  will  result  in strange bugs because the server will most
                likely ignore part of the headers you specified.
      
                The first line in a request (containing the  method,  usually  a
                GET  or  POST) is not a header and cannot be replaced using this
                option. Only the lines following the request-line  are  headers.
                Adding  this method line in this list of headers will only cause
                your request to send an invalid header.
      
                Pass a NULL to this to reset back to no custom headers.
      
                The most commonly  replaced  headers  have  "shortcuts"  in  the
                options CURLOPT_COOKIE (10022), CURLOPT_USERAGENT (10018) and CURLOPT_REFERER (10016).
      
             CURLOPT_HTTP200ALIASES (10104)
                Pass  a  pointer  to  a  linked list of aliases to be treated as
                valid HTTP 200 responses.  Some servers respond  with  a  custom
                header response line.  For example, IceCast servers respond with
                "ICY 200 OK".  By including this string in your list of aliases,
                the response will be treated as a valid HTTP header line such as
                "HTTP/1.0 200 OK". (Added in 7.10.3)
      
                The  linked  list  should  be  a  fully  valid  list  of  struct
                curl_slist   structs,   and   be   properly   filled   in.   Use
                curl_slist_append(3)     to     create     the     list      and
                curl_slist_free_all(3) to clean up an entire list.
      
                The  alias  itself is not parsed for any version strings. Before
                libcurl 7.16.3, Libcurl  used  the  value  set  by  option  CUR-
                LOPT_HTTP_VERSION,  but  starting  with  7.16.3  the protocol is
                assumed to match HTTP 1.0 when an alias matched.
      
             CURLOPT_COOKIE (10022)
                Pass a pointer to a zero terminated string as parameter. It will
                be  used  to set a cookie in the http request. The format of the
                string should be NAME=CONTENTS, where NAME is  the  cookie  name
                and CONTENTS is what the cookie should contain.
      
                If  you  need  to set multiple cookies, you need to set them all
                using a single option and thus you need to concatenate them  all
                in  one  single  string. Set multiple cookies in one string like
                this: "name1=content1; name2=content2;" etc.
      
                This option sets the cookie header  explictly  in  the  outgoing
                request(s). If multiple requests are done due to authentication,
                followed redirections or similar, they will all get this  cookie
                passed on.
      
                Using  this  option  multiple  times  will  only make the latest
                string override the previous ones.
      
             CURLOPT_COOKIE (10022)FILE
                Pass a pointer to a zero  terminated  string  as  parameter.  It
                should  contain  the  name  of  your file holding cookie data to
                read. The cookie data may be in Netscape / Mozilla  cookie  data
                format or just regular HTTP-style headers dumped to a file.
      
                Given  an  empty  or  non-existing  file or by passing the empty
                string (""), this option will enable cookies for this curl  han-
                dle,  making  it  understand and parse received cookies and then
                use matching cookies in future requests.
      
                If you use this option multiple times, you just add  more  files
                to read.  Subsequent files will add more cookies.
      
             CURLOPT_COOKIE (10022)JAR
                Pass  a  file  name  as  char *, zero terminated. This will make
                libcurl write all internally known cookies to the specified file
                when curl_easy_cleanup(3) is called. If no cookies are known, no
                file will be created. Specify "-" to instead  have  the  cookies
                written  to  stdout.  Using this option also enables cookies for
                this session, so if you for example follow a  location  it  will
                make matching cookies get sent accordingly.
      
                If  the cookie jar file can't be created or written to (when the
                curl_easy_cleanup(3) is called), libcurl  will  not  and  cannot
                report   an  error  for  this.  Using  CURLOPT_VERBOSE (41)  or  CUR-
                LOPT_DEBUGFUNCTION will get a warning to display,  but  that  is
                the  only  visible  feedback  you get about this possibly lethal
                situation.
      
             CURLOPT_COOKIE (10022)SESSION
                Pass a long set to 1 to mark this as a new cookie "session".  It
                will  force  libcurl  to  ignore all cookies it is about to load
                that  are  "session  cookies"  from  the  previous  session.  By
                default,  libcurl  always stores and loads all cookies, indepen-
                dent if they are session cookies or  not.  Session  cookies  are
                cookies  without  expiry date and they are meant to be alive and
                existing for this "session" only.
      
             CURLOPT_COOKIE (10022)LIST
                Pass a char * to a  cookie  string.  Cookie  can  be  either  in
                Netscape  /  Mozilla  format  or  just regular HTTP-style header
                (Set-Cookie: ...) format. If cURL cookie engine was not  enabled
                it  will enable its cookie engine.  Passing a magic string "ALL"
                will erase all cookies known by cURL. (Added in 7.14.1)  Passing
                the  special  string  "SESS" will only erase all session cookies
                known by cURL. (Added in  7.15.4)  Passing  the  special  string
                "FLUSH"  will write all cookies known by cURL to the file speci-
                fied by CURLOPT_COOKIE (10022)JAR.  (Added in 7.17.1)
      
             CURLOPT_HTTPGET (80)
                Pass a long. If the long is 1, this forces the HTTP  request  to
                get  back  to  GET.  Usable  if  a  POST, HEAD, PUT, or a custom
                request has been used previously using the same curl handle.
      
                When setting CURLOPT_HTTPGET (80) to 1,  it  will  automatically  set
                CURLOPT_NOBODY (44) to 0 (since 7.14.1).
      
             CURLOPT_HTTP_VERSION (84)
                Pass  a  long,  set  to  one of the values described below. They
                force libcurl to use the specific HTTP  versions.  This  is  not
                sensible to do unless you have a good reason.
      
                CURL_HTTP_VERSION_NONE
                   We  don't  care  about  what  version  the  library uses.
                   libcurl will use whatever it thinks fit.
      
                CURL_HTTP_VERSION_1_0
                   Enforce HTTP 1.0 requests.
      
                CURL_HTTP_VERSION_1_1
                   Enforce HTTP 1.1 requests.
      
             CURLOPT_IGNORE_CONTENT_LENGTH (136)
                Ignore the Content-Length header. This is useful for Apache  1.x
                (and similar servers) which will report incorrect content length
                for files over 2 gigabytes. If this option is  used,  curl  will
                not  be able to accurately report progress, and will simply stop
                the download when the server  ends  the  connection.  (added  in
                7.14.1)
      
             CURLOPT_HTTP_CONTENT_DECODING (158)
                Pass  a  long to tell libcurl how to act on content decoding. If
                set to zero, content decoding will be disabled. If set to  1  it
                is enabled. Libcurl has no default content decoding but requires
                you to use CURLOPT_ENCODING (10102) for that. (added in 7.16.2)
      
             CURLOPT_HTTP_TRANSFER_DECODING (157)
                Pass a long to tell libcurl how to act on transfer decoding.  If
                set  to zero, transfer decoding will be disabled, if set to 1 it
                is enabled (default). libcurl does chunked transfer decoding  by
                default unless this option is set to zero. (added in 7.16.2)
      
      TFTP OPTIONS
             CURLOPT_TFTP_BLKSIZE (178)
                Specify block size to use  for  TFTP  data  transmission.  Valid
                range as per RFC 2348 is 8-65464 bytes. The default of 512 bytes
                will be used if this option  is  not  specified.  The  specified
                block  size  will  only  be  used  pending support by the remote
                server. If the server does not return an option  acknowledgement
                or  returns  an  option  acknowledgement  with  no  blksize, the
                default of 512 bytes will be used. (added in 7.19.4)
      
      FTP OPTIONS
             CURLOPT_FTPPORT (10017)
                Pass a pointer to a zero terminated string as parameter. It will
                be  used  to get the IP address to use for the FTP PORT instruc-
                tion. The PORT instruction tells the remote server to connect to
                our  specified IP address. The string may be a plain IP address,
                a host name, a network interface name (under Unix) or just a '-'
                symbol  to let the library use your system's default IP address.
                Default FTP operations are passive, and thus won't use PORT.
      
                The address can be followed by a ':' to specify a port,  option-
                ally  followed  by  a  '-' to specify a port range.  If the port
                specified is 0, the operating system will pick a free port.   If
                a  range  is  provided and all ports in the range are not avail-
                able, libcurl will report CURLE_FTP_PORT_FAILED for the  handle.
                Invalid  port/range  settings  are ignored.  IPv6 addresses fol-
                lowed by a port or portrange  have  to  be  in  brackets.   IPv6
                addresses  without  port/range  specifier  can  be  in brackets.
                (added in 7.19.5)
      
                Examples with specified ports:
      
              eth0:0
              192.168.1.2:32000-33000
              curl.se:32123
              [::1]:1234-4567
      
                You disable PORT again and go back to using the passive  version
                by setting this option to NULL.
      
             CURLOPT_QUOTE (10028)
                Pass  a pointer to a linked list of FTP or SFTP commands to pass
                to the server prior to your  FTP  request.  This  will  be  done
                before  any  other commands are issued (even before the CWD com-
                mand for FTP). The linked list should be a fully valid  list  of
                'struct   curl_slist'  structs  properly  filled  in  with  text
                strings. Use curl_slist_append(3) to append  strings  (commands)
                to   the  list,  and  clear  the  entire  list  afterwards  with
                curl_slist_free_all(3). Disable this operation again by  setting
                a NULL to this option.  The set of valid FTP commands depends on
                the server (see RFC959 for a list of mandatory  commands).   The
                valid  SFTP  commands  are: chgrp, chmod, chown, ln, mkdir, pwd,
                rename, rm, rmdir, symlink (see curl(1)) (SFTP support added  in
                7.16.3)
      
             CURLOPT_POST (47)QUOTE (10039)
                Pass  a pointer to a linked list of FTP or SFTP commands to pass
                to the server after your FTP transfer request. The commands will
                only  be  run  if no error occurred. The linked list should be a
                fully valid list of struct curl_slist structs properly filled in
                as  described for CURLOPT_QUOTE (10028). Disable this operation again by
                setting a NULL to this option.
      
             CURLOPT_PREQUOTE (10093)
                Pass a pointer to a linked list of FTP commands to pass  to  the
                server after the transfer type is set. The linked list should be
                a fully valid list of struct curl_slist structs properly  filled
                in  as described for CURLOPT_QUOTE (10028). Disable this operation again
                by setting a NULL to this option. Before version 7.15.6, if  you
                also set CURLOPT_NOBODY (44) to 1, this option didn't work.
      
             CURLOPT_DIRLISTONLY (48)
                A parameter set to 1 tells the library to just list the names of
                files in a directory, instead of doing a full directory  listing
                that would include file sizes, dates etc. This works for FTP and
                SFTP URLs.
      
                This causes an FTP NLST command to be sent  on  an  FTP  server.
                Beware  that  some FTP servers list only files in their response
                to NLST; they might  not  include  subdirectories  and  symbolic
                links.
      
                Setting  this  option to 1 also implies a directory listing even
                if the URL doesn't end with a slash, which otherwise  is  neces-
                sary.
      
                Do  NOT use this option if you also use CURLOPT_WILDCARDMATCH (197) as
                it will effectively break that feature then.
      
                (This option was known as CURLOPT_FTPLISTONLY up to 7.16.4)
      
             CURLOPT_APPEND (50)
                A parameter set to 1 tells the library to append to  the  remote
                file instead of overwrite it. This is only useful when uploading
                to an FTP site.
      
                (This option was known as CURLOPT_FTPAPPEND up to 7.16.4)
      
             CURLOPT_FTP_USE_EPRT (106)
                Pass a long. If the value is 1, it tells curl to  use  the  EPRT
                (and  LPRT)  command  when  doing active FTP downloads (which is
                enabled by CURLOPT_FTPPORT (10017)). Using EPRT means that it will first
                attempt  to use EPRT and then LPRT before using PORT, but if you
                pass zero to this option, it will not try using  EPRT  or  LPRT,
                only plain PORT. (Added in 7.10.5)
      
                If  the  server is an IPv6 host, this option will have no effect
                as of 7.12.3.
      
             CURLOPT_FTP_USE_EPSV (85)
                Pass a long. If the value is 1, it tells curl to  use  the  EPSV
                command  when  doing passive FTP downloads (which it always does
                by default). Using EPSV means that it will first attempt to  use
                EPSV  before using PASV, but if you pass zero to this option, it
                will not try using EPSV, only plain PASV.
      
                If the server is an IPv6 host, this option will have  no  effect
                as of 7.12.3.
      
             CURLOPT_FTP_USE_PRET (188)
                Pass  a  long.  If  the value is 1, it tells curl to send a PRET
                command before PASV (and  EPSV).  Certain  FTP  servers,  mainly
                drftpd, require this non-standard command for directory listings
                as well as up and downloads in PASV mode.  Has  no  effect  when
                using the active FTP transfers mode.  (Added in 7.20.0)
      
             CURLOPT_FTP_CREATE_MISSING_DIRS (110)
                Pass  a long. If the value is 1, curl will attempt to create any
                remote directory that it fails to CWD into. CWD is  the  command
                that changes working directory. (Added in 7.10.7)
      
                This setting also applies to SFTP-connections. curl will attempt
                to create the remote directory if it can't obtain  a  handle  to
                the  target-location.  The  creation  will fail if a file of the
                same name as the directory to create already exists or  lack  of
                permissions prevents creation. (Added in 7.16.3)
      
                Starting  with  7.19.4,  you can also set this value to 2, which
                will make libcurl retry the CWD command again if the  subsequent
                MKD  command  fails.  This  is especially useful if you're doing
                many simultanoes connections against the same  server  and  they
                all  have  this  option  enabled, as then CWD may first fail but
                then another connection does MKD before this connection and thus
                MKD  fails  but  trying  CWD  works!  7.19.4 also introduced the
                CURLFTP_CREATE_DIR and CURLFTP_CREATE_DIR_RETRY enum  names  for
                these arguments.
      
                Before  version 7.19.4, libcurl will simply ignore arguments set
                to 2 and act as if 1 was selected.
      
             CURLOPT_FTP_RESPONSE_TIMEOUT (112)
                Pass a long.  Causes curl to set a timeout period  (in  seconds)
                on  the  amount  of  time  that the server is allowed to take in
                order to generate a response message for a  command  before  the
                session  is  considered  hung.   While  curl  is  waiting  for a
                response, this value overrides  CURLOPT_TIMEOUT (13). It  is  recom-
                mended that if used in conjunction with CURLOPT_TIMEOUT (13), you set
                CURLOPT_FTP_RESPONSE_TIMEOUT (112)  to    a  value  smaller  than   CUR-
                LOPT_TIMEOUT.  (Added in 7.10.8)
      
             CURLOPT_FTP_ALTERNATIVE_TO_USER (10147)
                Pass  a  char * as parameter, pointing to a string which will be
                used to authenticate if the usual  FTP  "USER  user"  and  "PASS
                password"  negotiation fails. This is currently only known to be
                required when connecting to Tumbleweed's Secure  Transport  FTPS
                server  using  client certificates for authentication. (Added in
                7.15.5)
      
             CURLOPT_FTP_SKIP_PASV_IP (137)
                Pass a long. If set to 1, it instructs libcurl to not use the IP
                address  the  server  suggests  in its 227-response to libcurl's
                PASV command when libcurl connects the data connection.  Instead
                libcurl  will re-use the same IP address it already uses for the
                control connection. But it will use the  port  number  from  the
                227-response. (Added in 7.14.2)
      
                This  option has no effect if PORT, EPRT or EPSV is used instead
                of PASV.
      
             CURLOPT_USE_SSL (119)
                Pass a long using one of the values from below, to make  libcurl
                use  your  desired  level of SSL for the FTP transfer. (Added in
                7.11.0)
      
                (This option was known as CURLOPT_FTP_SSL up to 7.16.4, and  the
                constants were known as CURLFTPSSL_*)
      
                CURLUSESSL_NONE
                   Don't attempt to use SSL.
      
                CURLUSESSL_TRY
                   Try using SSL, proceed as normal otherwise.
      
                CURLUSESSL_CONTROL
                   Require  SSL  for  the  control  connection  or fail with
                   CURLE_USE_SSL_FAILED.
      
                CURLUSESSL_ALL
                   Require  SSL  for  all   communication   or   fail   with
                   CURLE_USE_SSL_FAILED.
      
             CURLOPT_FTPSSLAUTH (129)
                Pass  a  long  using  one of the values from below, to alter how
                libcurl issues "AUTH TLS" or "AUTH SSL" when  FTP  over  SSL  is
                activated (see CURLOPT_USE_SSL (119)). (Added in 7.12.2)
      
                CURLFTPAUTH_DEFAULT
                   Allow libcurl to decide.
      
                CURLFTPAUTH_SSL
                   Try  "AUTH  SSL"  first, and only if that fails try "AUTH
                   TLS".
      
                CURLFTPAUTH_TLS
                   Try "AUTH TLS" first, and only if that  fails  try  "AUTH
                   SSL".
      
             CURLOPT_FTP_SSL_CCC (154)
                If  enabled,  this  option  makes libcurl use CCC (Clear Command
                Channel). It shuts down the SSL/TLS layer after  authenticating.
                The  rest  of  the  control  channel communication will be unen-
                crypted. This allows NAT routers to follow the FTP  transaction.
                Pass a long using one of the values below.  (Added in 7.16.1)
      
                CURLFTPSSL_CCC_NONE
                   Don't attempt to use CCC.
      
                CURLFTPSSL_CCC_PASSIVE
                   Do  not initiate the shutdown, but wait for the server to
                   do it. Do not send a reply.
      
                CURLFTPSSL_CCC_ACTIVE
                   Initiate the shutdown and wait for a reply.
      
             CURLOPT_FTP_ACCOUNT (10134)
                Pass a pointer to a zero-terminated string (or NULL to disable).
                When  an  FTP server asks for "account data" after user name and
                password has been provided, this data is sent off using the ACCT
                command. (Added in 7.13.0)
      
             CURLOPT_FTP_FILEMETHOD (138)
                Pass  a  long that should have one of the following values. This
                option controls what method libcurl should use to reach  a  file
                on  a FTP(S) server. The argument should be one of the following
                alternatives:
      
                CURLFTPMETHOD_MULTICWD
                   libcurl does a single CWD operation for each path part in
                   the  given URL. For deep hierarchies this means many com-
                   mands. This is how RFC1738 says it should be  done.  This
                   is the default but the slowest behavior.
      
                CURLFTPMETHOD_NOCWD
                   libcurl  does  no CWD at all. libcurl will do SIZE, RETR,
                   STOR etc and give a full path to the server for all these
                   commands. This is the fastest behavior.
      
                CURLFTPMETHOD_SINGLECWD
                   libcurl  does  one CWD with the full target directory and
                   then operates on the file "normally" (like in the  multi-
                   cwd case). This is somewhat more standards compliant than
                   'nocwd' but without the full penalty of 'multicwd'.
             (Added in 7.15.1)
      
      PROTOCOL OPTIONS
             CURLOPT_TRANSFERTEXT (53)
                A parameter set to 1 tells the library to use ASCII mode for FTP
                transfers,  instead  of  the  default binary transfer. For win32
                systems it does not set the stdout to binary mode.  This  option
                can  be  usable when transferring text data between systems with
                different views on certain characters, such as newlines or simi-
                lar.
      
                libcurl does not do a complete ASCII conversion when doing ASCII
                transfers over FTP. This is a known limitation/flaw that  nobody
                has  rectified.  libcurl  simply sets the mode to ASCII and per-
                forms a standard transfer.
      
             CURLOPT_PROXY (10004)_TRANSFER_MODE
                Pass a long. If the value is set to 1 (one), it tells libcurl to
                set  the  transfer mode (binary or ASCII) for FTP transfers done
                via an HTTP proxy, by appending ;type=a or ;type=i to  the  URL.
                Without  this setting, or it being set to 0 (zero, the default),
                CURLOPT_TRANSFERTEXT (53) has no effect when doing FTP via  a proxy.
                Beware  that  not  all  proxies support this feature.  (Added in
                7.18.0)
      
             CURLOPT_CRLF (27)
                Convert Unix newlines to CRLF newlines on transfers.
      
             CURLOPT_RANGE (10007)
                Pass a char * as parameter, which should contain  the  specified
                range  you  want. It should be in the format "X-Y", where X or Y
                may be left out. HTTP transfers also support several  intervals,
                separated with commas as in "X-Y,N-M". Using this kind of multi-
                ple intervals will cause the HTTP server to  send  the  response
                document  in pieces (using standard MIME separation techniques).
                For RTSP, the formatting of a range should follow RFC 2326  Sec-
                tion  12.29.  For  RTSP, byte ranges are not permitted. Instead,
                ranges should be given in npt, utc, or smpte formats.
      
                Pass a NULL to this option to disable the use of ranges.
      
                Ranges work on HTTP, FTP, FILE (since 7.18.0), and  RTSP  (since
                7.20.0) transfers only.
      
             CURLOPT_RESUME_FROM (21)
                Pass  a  long  as parameter. It contains the offset in number of
                bytes that you want the transfer to start from. Set this  option
                to  0 to make the transfer start from the beginning (effectively
                disabling resume). For FTP, set this option to -1  to  make  the
                transfer  start  from the end of the target file (useful to con-
                tinue an interrupted upload).
      
                When doing uploads with FTP, the resume position is where in the
                local/source  file  libcurl should try to resume the upload from
                and it will then append the source file  to  the  remote  target
                file.
      
             CURLOPT_RESUME_FROM_LARGE (21)
                Pass a curl_off_t as parameter. It contains the offset in number
                of bytes that you want the transfer to  start  from.  (Added  in
                7.11.0)
      
             CURLOPT_CUSTOMREQUEST (10036)
                Pass a pointer to a zero terminated string as parameter. It will
                be used instead of GET or HEAD when doing an  HTTP  request,  or
                instead of LIST or NLST when doing a FTP directory listing. This
                is useful for doing DELETE or other more or  less  obscure  HTTP
                requests.  Don't do this at will, make sure your server supports
                the command first.
      
                When you change the request method by setting  CURLOPT_CUSTOMRE-
                QUEST  to  something,  you  don't  actually  change  how libcurl
                behaves or acts in regards to the particular request method,  it
                will only change the actual string sent in the request.
      
                For  example: if you tell libcurl to do a HEAD request, but then
                change the request to a "GET" with CURLOPT_CUSTOMREQUEST (10036)  you'll
                still  see  libcurl  act  as if it sent a HEAD even when it does
                send a GET.
      
                To switch to a proper HEAD, use CURLOPT_NOBODY (44), to switch  to  a
                proper POST, use CURLOPT_POST (47) or CURLOPT_POST (47)FIELDS (10015) and so on.
      
                Restore to the internal default by setting this to NULL.
      
                Many  people have wrongly used this option to replace the entire
                request with their own, including multiple headers and POST con-
                tents.  While  that  might  work  in  many  cases, it will cause
                libcurl to send invalid requests and it could  possibly  confuse
                the remote server badly. Use CURLOPT_POST (47) and CURLOPT_POST (47)FIELDS (10015)
                to set POST data. Use CURLOPT_HTTPHEADER (10023) to  replace  or  extend
                the  set of headers sent by libcurl. Use CURLOPT_HTTP_VERSION (84) to
                change HTTP version.
      
             CURLOPT_FILETIME (10001)
                Pass a long. If it is 1, libcurl will attempt to get the modifi-
                cation  date  of  the  remote  document  in this operation. This
                requires that the remote server sends the time or replies  to  a
                time  querying  command.  The curl_easy_getinfo(3) function with
                the CURLINFO_FILETIME argument can be used after a  transfer  to
                extract the received time (if any).
      
             CURLOPT_NOBODY (44)
                A  parameter set to 1 tells the library to not include the body-
                part in the output. This is only  relevant  for  protocols  that
                have  separate  header  and body parts. On HTTP(S) servers, this
                will make libcurl do a HEAD request.
      
                To change request to GET, you should use CURLOPT_HTTPGET (80). Change
                request to POST with CURLOPT_POST (47) etc.
      
             CURLOPT_INFILESIZE (10009)
                When  uploading  a  file to a remote site, this option should be
                used to tell libcurl what the expected size of  the  infile  is.
                This  value should be passed as a long. See also CURLOPT_INFILE (10009)-
                SIZE_LARGE.
      
                For uploading using SCP, this option or CURLOPT_INFILE (10009)SIZE_LARGE
                is mandatory.
      
                This  option  does not limit how much data libcurl will actually
                send, as that is controlled entirely by what the  read  callback
                returns.
      
             CURLOPT_INFILESIZE_LARGE (10009)
                When  uploading  a  file to a remote site, this option should be
                used to tell libcurl what the expected size of  the  infile  is.
                This value should be passed as a curl_off_t. (Added in 7.11.0)
      
                For  uploading  using  SCP, this option or CURLOPT_INFILE (10009)SIZE is
                mandatory.
      
                This option does not limit how much data libcurl  will  actually
                send,  as  that is controlled entirely by what the read callback
                returns.
      
             CURLOPT_UPLOAD (46)
                A parameter set to 1 tells the library to prepare for an upload.
                The  CURLOPT_READDATA (10009)  and CURLOPT_INFILESIZE (10009) or CURLOPT_INFILESIZE_LARGE (10009)-
                options are also interesting for uploads. If the pro-
                tocol  is HTTP, uploading means using the PUT request unless you
                tell libcurl otherwise.
      
                Using PUT with HTTP 1.1 implies the use of a  "Expect:  100-con-
                tinue"  header.   You can disable this header with CURLOPT_HTTP-
                HEADER as usual.
      
                If you use PUT to a HTTP 1.1 server, you can upload data without
                knowing the size before starting the transfer if you use chunked
                encoding. You enable this by adding  a  header  like  "Transfer-
                Encoding:  chunked"  with  CURLOPT_HTTPHEADER (10023).  With HTTP 1.0 or
                without chunked transfer, you must specify the size.
      
             CURLOPT_MAXFILESIZE (114)
                Pass a long as parameter. This allows you to specify the maximum
                size  (in bytes) of a file to download. If the file requested is
                larger  than  this  value,  the  transfer  will  not  start  and
                CURLE_FILESIZE_EXCEEDED will be returned.
      
                The  file  size  is  not always known prior to download, and for
                such files this option has no effect even if the  file  transfer
                ends  up  being larger than this given limit. This concerns both
                FTP and HTTP transfers.
      
             CURLOPT_MAXFILESIZE_LARGE (114)
                Pass a curl_off_t as parameter. This allows you to  specify  the
                maximum  size  (in  bytes)  of  a  file to download. If the file
                requested is larger than this value, the transfer will not start
                and CURLE_FILESIZE_EXCEEDED will be returned. (Added in 7.11.0)
      
                The  file  size  is  not always known prior to download, and for
                such files this option has no effect even if the  file  transfer
                ends  up  being larger than this given limit. This concerns both
                FTP and HTTP transfers.
      
             CURLOPT_TIMECONDITION (33)
                Pass a long as parameter. This defines how the CURLOPT_TIMEVALUE (34)
                time  value is treated. You can set this parameter to CURL_TIME-
                COND_IFMODSINCE  or  CURL_TIMECOND_IFUNMODSINCE.  This   feature
                applies to HTTP, FTP, and RTSP.
      
                The  last modification time of a file is not always known and in
                such instances this feature will have  no  effect  even  if  the
                given  time  condition  would  not have been met. curl_easy_get-
                info(3) with the CURLINFO_CONDITION_UNMET  option  can  be  used
                after  a  transfer to learn if a zero-byte successful "transfer"
                was due to this condition not matching.
      
             CURLOPT_TIMEVALUE (34)
                Pass a long as parameter. This should be  the  time  in  seconds
                since  1  Jan  1970, and the time will be used in a condition as
                specified with CURLOPT_TIMECONDITION (33).
      
      CONNECTION OPTIONS
             CURLOPT_TIMEOUT (13)
                Pass a long as parameter containing the maximum time in  seconds
                that you allow the libcurl transfer operation to take. Normally,
                name lookups can take a considerable time  and  limiting  opera-
                tions  to less than a few minutes risk aborting perfectly normal
                operations. This option will cause curl to use  the  SIGALRM  to
                enable time-outing system calls.
      
                In unix-like systems, this might cause signals to be used unless
                CURLOPT_NOSIGNAL (99) is set.
      
             CURLOPT_TIMEOUT_MS (13)
                Like CURLOPT_TIMEOUT (13) but takes number of milliseconds  instead.
                If  libcurl  is  built to use the standard system name resolver,
                that portion of the transfer will still use full-second  resolu-
                tion  for timeouts with a minimum timeout allowed of one second.
                (Added in 7.16.2)
      
             CURLOPT_LOW_SPEED_LIMIT (19)
                Pass a long as parameter. It  contains  the  transfer  speed  in
                bytes  per  second that the transfer should be below during CUR-
                LOPT_LOW_SPEED_TIME seconds for the library to consider  it  too
                slow and abort.
      
             CURLOPT_LOW_SPEED_TIME (20)
                Pass  a  long as parameter. It contains the time in seconds that
                the transfer should be below the CURLOPT_LOW_SPEED_LIMIT (19) for the
                library to consider it too slow and abort.
      
             CURLOPT_MAX_SEND_SPEED_LARGE (30145)
                Pass a curl_off_t as parameter.  If an upload exceeds this speed
                (counted in bytes per second) on cumulative average  during  the
                transfer,  the transfer will pause to keep the average rate less
                than or equal to the parameter  value.   Defaults  to  unlimited
                speed. (Added in 7.15.5)
      
             CURLOPT_MAX_RECV_SPEED_LARGE (30146)
                Pass  a  curl_off_t  as  parameter.   If a download exceeds this
                speed (counted in bytes per second) on cumulative average during
                the  transfer,  the transfer will pause to keep the average rate
                less than or equal to the parameter value. Defaults to unlimited
                speed. (Added in 7.15.5)
      
             CURLOPT_MAXCONNECTS (71)
                Pass  a  long.  The set number will be the persistent connection
                cache size. The set amount will be the maximum amount of  simul-
                taneously  open  connections that libcurl may cache in this easy
                handle. Default is 5, and there isn't  much  point  in  changing
                this  value unless you are perfectly aware of how this works and
                changes libcurl's behaviour. This concerns connections using any
                of the protocols that support persistent connections.
      
                When  reaching  the maximum limit, curl closes the oldest one in
                the cache to prevent increasing the number of open  connections.
      
                If  you  already have performed transfers with this curl handle,
                setting a smaller MAXCONNECTS than before may cause open connec-
                tions to get closed unnecessarily.
      
                If  you  add this easy handle to a multi handle, this setting is
                not acknowledged, and you must instead use  curl_multi_setopt(3)
                and the CURLMOPT_MAXCONNECTS option.
      
             CURLOPT_CLOSEPOLICY (72)
                (Obsolete) This option does nothing.
      
             CURLOPT_FRESH_CONNECT (74)
                Pass  a  long.  Set  to  1  to  make the next transfer use a new
                (fresh) connection by force. If the  connection  cache  is  full
                before  this connection, one of the existing connections will be
                closed as according to the  selected  or  default  policy.  This
                option  should  be  used with caution and only if you understand
                what it does. Set this to 0 to have libcurl attempt re-using  an
                existing connection (default behavior).
      
             CURLOPT_FORBID_REUSE (75)
                Pass a long. Set to 1 to make the next transfer explicitly close
                the connection when done. Normally, libcurl  keeps  all  connec-
                tions alive when done with one transfer in case a succeeding one
                follows that can re-use them.  This option should be  used  with
                caution  and  only  if  you understand what it does. Set to 0 to
                have libcurl keep the connection open for possible later  re-use
                (default behavior).
      
             CURLOPT_CONNECTTIMEOUT (78)
                Pass  a long. It should contain the maximum time in seconds that
                you allow the connection to the server to take.  This only  lim-
                its  the connection phase, once it has connected, this option is
                of no more use. Set to zero to disable  connection  timeout  (it
                will  then  only timeout on the system's internal timeouts). See
                also the CURLOPT_TIMEOUT (13) option.
      
                In unix-like systems, this might cause signals to be used unless
                CURLOPT_NOSIGNAL (99) is set.
      
             CURLOPT_CONNECTTIMEOUT_MS (78)
                Like CURLOPT_CONNECTTIMEOUT (78) but takes the number of milliseconds
                instead. If libcurl is built to use  the  standard  system  name
                resolver, that portion of the connect will still use full-second
                resolution for timeouts with a minimum timeout  allowed  of  one
                second.  (Added in 7.16.2)
      
             CURLOPT_IPRESOLVE (113)
                Allows an application to select what kind of IP addresses to use
                when resolving host names. This is only interesting  when  using
                host names that resolve addresses using more than one version of
                IP. The allowed values are:
      
                CURL_IPRESOLVE_WHATEVER
                   Default, resolves addresses to all IP versions that  your
                   system allows.
      
                CURL_IPRESOLVE_V4 (1)
                   Resolve to IPv4 addresses.
      
                CURL_IPRESOLVE_V6 (2)
                   Resolve to IPv6 addresses.
      
             CURLOPT_CONNECT_ONLY (141)
                Pass  a long. If the parameter equals 1, it tells the library to
                perform all the required  proxy  authentication  and  connection
                setup, but no data transfer.  This option is useful only on HTTP
                URLs.
      
                This option is useful with  the  CURLINFO_LASTSOCKET  option  to
                curl_easy_getinfo(3).  The library can set up the connection and
                then the application can obtain the most  recently  used  socket
                for special data transfers. (Added in 7.15.2)
      
      SSL and SECURITY OPTIONS
             CURLOPT_SSLCERT (10025)
                Pass  a  pointer  to  a zero terminated string as parameter. The
                string should be the file name of your certificate. The  default
                format is "PEM" and can be changed with CURLOPT_SSLCERT (10025)TYPE.
      
                With  NSS  this  is  the nickname of the certificate you wish to
                authenticate with.
      
             CURLOPT_SSLCERTTYPE (10025)
                Pass a pointer to a zero terminated  string  as  parameter.  The
                string  should be the format of your certificate. Supported for-
                mats are "PEM" and "DER".  (Added in 7.9.3)
      
             CURLOPT_SSLKEY (10087)
                Pass a pointer to a zero terminated  string  as  parameter.  The
                string  should be the file name of your private key. The default
                format is "PEM" and can be changed with CURLOPT_SSLKEY (10087)TYPE.
      
             CURLOPT_SSLKEYTYPE (10087)
                Pass a pointer to a zero terminated  string  as  parameter.  The
                string  should be the format of your private key. Supported for-
                mats are "PEM", "DER" and "ENG".
      
                The format "ENG" enables you to load  the  private  key  from  a
                crypto engine. In this case CURLOPT_SSLKEY (10087) is used as an identi-
                fier passed to the engine. You have to  set  the  crypto  engine
                with  CURLOPT_SSLENGINE (10089).   "DER"  format key file currently does
                not work because of a bug in OpenSSL.
      
             CURLOPT_KEYPASSWD (10026)
                Pass a pointer to a zero terminated string as parameter. It will
                be  used  as  the password required to use the CURLOPT_SSLKEY (10087) or
                CURLOPT_SSH_PRIVATE_KEYFILE (10153) private key.   You  never  needed  a
                pass  phrase to load a certificate but you need one to load your
                private key.
      
                (This option was known as CURLOPT_SSLKEY (10087)PASSWD up to 7.16.4  and
                CURLOPT_SSLCERT (10025)PASSWD up to 7.9.2)
      
             CURLOPT_SSLENGINE (10089)
                Pass a pointer to a zero terminated string as parameter. It will
                be used as the identifier for the crypto engine you want to  use
                for your private key.
      
                If the crypto device cannot be loaded, CURLE_SSL_ENGINE_NOTFOUND
                is returned.
      
             CURLOPT_SSLENGINE_DEFAULT (10089)
                Sets the actual crypto engine as the  default  for  (asymmetric)
                crypto operations.
      
                If  the  crypto device cannot be set, CURLE_SSL_ENGINE_SETFAILED
                is returned.
      
                Even though this option doesn't need any parameter, in some con-
                figurations  curl_easy_setopt might be defined as a macro taking
                exactly three arguments. Therefore, it's recommended to  pass  1
                as parameter to this option.
      
             CURLOPT_SSLVERSION (32)
                Pass  a  long as parameter to control what version of SSL/TLS to
                attempt to use.  The available options are:
      
                CURL_SSLVERSION_DEFAULT
                   The default action. This will attempt to figure  out  the
                   remote  SSL  protocol version, i.e. either SSLv3 or TLSv1
                   (but not SSLv2, which became  disabled  by  default  with
                   7.18.1).
      
                CURL_SSLVERSION_TLSv1
                   Force TLSv1
      
                CURL_SSLVERSION_SSLv2
                   Force SSLv2
      
                CURL_SSLVERSION_SSLv3
                   Force SSLv3
      
             CURLOPT_SSL_VERIFYPEER (64)
                Pass a long as parameter.
      
                This option determines whether curl verifies the authenticity of
                the peer's certificate. A value of 1 means curl  verifies;  zero
                means  it  doesn't.  The default is nonzero, but before 7.10, it
                was zero.
      
                When negotiating an SSL connection, the server sends a  certifi-
                cate  indicating  its  identity.  Curl verifies whether the cer-
                tificate is authentic, i.e. that you can trust that  the  server
                is  who  the  certificate  says it is.  This trust is based on a
                chain of digital signatures, rooted in  certification  authority
                (CA)  certificates  you  supply.   As  of  7.10, curl installs a
                default bundle of CA certificates and you can specify  alternate
                certificates  with the CURLOPT_CAINFO (10065) option or the CURLOPT_CAP-
                ATH option.
      
                When CURLOPT_SSL_VERIFYPEER (64) is  nonzero, and  the  verification
                fails to prove that the certificate is authentic, the connection
                fails.  When the option is zero, the connection succeeds regard-
                less.
      
                Authenticating  the  certificate  is  not by itself very useful.
                You typically want to ensure that the server,  as  authentically
                identified  by  its  certificate,  is  the server you mean to be
                talking to.  Use CURLOPT_SSL_VERIFYHOST (81) to control that.
      
             CURLOPT_CAINFO (10065)
                Pass a char * to a zero terminated string naming a file  holding
                one  or  more  certificates to verify the peer with.  This makes
                sense only when used in combination with  the  CURLOPT_SSL_VERI-
                FYPEER   option.    If   CURLOPT_SSL_VERIFYPEER (64)  is  zero,  CUR-
                LOPT_CAINFO need not even indicate an accessible file.
      
                This option is by default set to the system path where libcurl's
                cacert  bundle  is assumed to be stored, as established at build
                time.
      
                When built against NSS, this is the directory that the NSS  cer-
                tificate database resides in.
      
             CURLOPT_ISSUERCERT (10170)
                Pass  a char * to a zero terminated string naming a file holding
                a CA certificate in PEM format. If the option is set,  an  addi-
                tional check against the peer certificate is performed to verify
                the issuer is indeed the one  associated  with  the  certificate
                provided  by  the  option.  This  additional  check is useful in
                multi-level PKI where one needs to enforce that  the  peer  cer-
                tificate is from a specific branch of the tree.
      
                This  option  makes sense only when used in combination with the
                CURLOPT_SSL_VERIFYPEER (64) option.  Otherwise,  the  result  of  the
                check is not considered as failure.
      
                A  specific  error code (CURLE_SSL_ISSUER_ERROR) is defined with
                the option, which is returned if the setup of the  SSL/TLS  ses-
                sion  has  failed due to a mismatch with the issuer of peer cer-
                tificate (CURLOPT_SSL_VERIFYPEER (64) has to be set too for the check
                to fail). (Added in 7.19.0)
      
             CURLOPT_CAPATH (10097)
                Pass  a  char  *  to a zero terminated string naming a directory
                holding multiple CA certificates to verify the  peer  with.  The
                certificate   directory  must  be  prepared  using  the  openssl
                c_rehash utility. This makes sense only when used in combination
                with  the  CURLOPT_SSL_VERIFYPEER (64)  option.  If CURLOPT_SSL_VERI-
                FYPEER is zero, CURLOPT_CAPATH (10097) need not even indicate an  acces-
                sible  path.   The  CURLOPT_CAPATH (10097)  function apparently does not
                work in Windows due to some limitation in openssl.  This  option
                is  OpenSSL-specific and does nothing if libcurl is built to use
                GnuTLS.
      
             CURLOPT_CRLFILE  (27)
                Pass a char * to a zero terminated string naming a file with the
                concatenation  of  CRL (in PEM format) to use in the certificate
                validation that occurs during the SSL exchange.
      
                When curl is built to use NSS or GnuTLS,  there  is  no  way  to
                influence  the  use  of  CRL  passed to help in the verification
                process.  When  libcurl   is   built   with   OpenSSL   support,
                X509_V_FLAG_CRL_CHECK  and  X509_V_FLAG_CRL_CHECK_ALL  are  both
                set, requiring CRL check against all the elements  of  the  cer-
                tificate chain if a CRL file is passed.
      
                This  option  makes sense only when used in combination with the
                CURLOPT_SSL_VERIFYPEER (64) option.
      
                A specific error code (CURLE_SSL_CRL_BADFILE)  is  defined  with
                the  option.  It is returned when the SSL exchange fails because
                the CRL file cannot be loaded.  A failure in certificate verifi-
                cation due to a revocation information found in the CRL does not
                trigger this specific error. (Added in 7.19.0)
      
             CURLOPT_CERTINFO (172)
                Pass a long set to 1 to enable libcurl's certificate chain  info
                gatherer.  With  this  enabled,  libcurl (if built with OpenSSL)
                will extract lots of information and data about the certificates
                in  the  certificate chain used in the SSL connection. This data
                is  then  possible   to   extract   after   a   transfer   using
                curl_easy_getinfo(3) and its option CURLINFO_CERTINFO. (Added in
                7.19.1)
      
             CURLOPT_RANDOM_FILE (10076)
                Pass a char * to a zero terminated file name. The file  will  be
                used  to  read  from to seed the random engine for SSL. The more
                random the specified file is, the more secure the SSL connection
                will become.
      
             CURLOPT_EGDSOCKET (10077)
                Pass  a  char  * to the zero terminated path name to the Entropy
                Gathering Daemon socket. It will be  used  to  seed  the  random
                engine for SSL.
      
             CURLOPT_SSL_VERIFYHOST (81)
                Pass a long as parameter.
      
                This  option determines whether libcurl verifies that the server
                cert is for the server it is known as.
      
                When negotiating a SSL connection, the server sends  a  certifi-
                cate indicating its identity.
      
                When CURLOPT_SSL_VERIFYHOST (81) is 2, that certificate must indicate
                that the server is the server to which you meant to connect,  or
                the connection fails.
      
                Curl  considers the server the intended one when the Common Name
                field or a Subject  Alternate  Name  field  in  the  certificate
                matches  the host name in the URL to which you told Curl to con-
                nect.
      
                When the value is 1, the certificate must contain a Common  Name
                field,  but  it  doesn't matter what name it says.  (This is not
                ordinarily a useful setting).
      
                When the value is 0, the connection succeeds regardless  of  the
                names in the certificate.
      
                The default, since 7.10, is 2.
      
                This  option  controls  checking  the server's claimed identity.
                The  server  could  be  lying.   To  control  lying,  see   CUR-
                LOPT_SSL_VERIFYPEER.
      
             CURLOPT_SSL_CIPHER_LIST (10083)
                Pass  a char *, pointing to a zero terminated string holding the
                list of ciphers to use for the SSL connection. The list must  be
                syntactically correct, it consists of one or more cipher strings
                separated by colons. Commas or spaces are also acceptable  sepa-
                rators  but  colons are normally used, !, - and + can be used as
                operators.
      
                For OpenSSL and GnuTLS valid examples of  cipher  lists  include
                'RC4-SHA',  'SHA1+DES',  'TLSv1' and 'DEFAULT'. The default list
                is normally set when you compile OpenSSL.
      
                You'll find  more  details  about  cipher  lists  on  this  URL:
                http://www.openssl.org/docs/apps/ciphers.html
      
                For    NSS,    valid    examples   of   cipher   lists   include
                'rsa_rc4_128_md5', 'rsa_aes_128_sha', etc. With  NSS  you  don't
                add/remove  ciphers.  If  one  uses  this  option then all known
                ciphers are disabled and only those passed in are enabled.
      
                You'll find more details about the NSS cipher lists on this URL:
                http://directory.fedora.redhat.com/docs/mod_nss.html#Directives
      
      
             CURLOPT_SSL_SESSIONID_CACHE (150)
                Pass  a long set to 0 to disable libcurl's use of SSL session-ID
                caching. Set this to 1 to enable it. By  default  all  transfers
                are  done using the cache. While nothing ever should get hurt by
                attempting to reuse SSL session-IDs, there seem to be broken SSL
                implementations in the wild that may require you to disable this
                in order for you to succeed. (Added in 7.16.0)
      
             CURLOPT_KRBLEVEL (10063)
                Pass a char * as parameter. Set the kerberos security level  for
                FTP;  this  also  enables kerberos awareness.  This is a string,
                'clear', 'safe', 'confidential' or 'private'.  If the string  is
                set  but doesn't match one of these, 'private' will be used. Set
                the string to NULL to disable kerberos support for FTP.
      
                (This option was known as CURLOPT_KRB4LEVEL up to 7.16.3)
      
      [...]
      
      

Element Content

The content of the element is an option-specific string that depends on the option being set.

Examples

Restrict transport to IPv4
<TransportOption provider="CURL" option="113">1</TransportOption>
Set transport timeout in seconds
<TransportOption provider="CURL" option="13">120</TransportOption>
Set HTTP proxy address
<TransportOption provider="CURL" option="10004">proxy.example.org:8080</TransportOption>
Verify SSL certificate
<!-- Known to work with curl 7.26 and GnuTLS 2.12.20 (Debian 7.0) -->
<TransportOption provider="CURL" option="64">1</TransportOption>
<TransportOption provider="CURL" option="81">2</TransportOption>
<TransportOption provider="CURL" option="10065">/etc/ssl/certs/ca-certificates.crt</TransportOption>

OpenSSL Provider (Version 2.4 and Above)

When provider is set to "OpenSSL", the following information applies.

Attributes

  • option(string)
    • The only supported value is currently "SSL_OP_ALLOW_UNSAFE_LEGACY_RENEGOTIATION". If the element content is "1" or "true", this causes the option for unsafe renegotiation to be applied, allowing interop with older servers when using very recent versions of OpenSSL.

Element Content

The content of the element is an option-specific string that depends on the option being set.