           curl_easy_setopt - set options for a curl easy handle

## SYNOPSIS

           #include <curl/curl.h>

           CURLcode curl_easy_setopt(CURL *handle, CURLoption option,
           parameter);

## DESCRIPTION

           curl_easy_setopt() is used to tell libcurl how to  behave.
           By  using the appropriate options to curl_easy_setopt, you
           can change libcurl's behavior.  All options are  set  with
           the  option followed by a parameter. That parameter can be
           a long, a function  pointer  or  an  object  pointer,  all
           depending  on  what the specific option expects. Read this
           manual carefully as bad input values may cause libcurl  to
           behave  badly!   You can only set one option in each func-
           tion   call.   A    typical    application    uses    many
           curl_easy_setopt() calls in the setup phase.

           NOTE:  strings  passed  to  libcurl as 'char *' arguments,
           will not be copied by the library. Instead you should keep
           them available until libcurl no longer needs them. Failing
           to do so will cause very odd  behavior  or  even  crashes.
           libcurl  will need them until you call curl_easy_cleanup()
           or you set the  same  option  again  to  use  a  different
           pointer.

           NOTE2:  options  set with this function call are valid for
           the forthcoming data transfers that are performed when you
           invoke  curl_easy_perform.  The options are not in any way
           reset between transfers, so if you want subsequent  trans-
           fers  with different options, you must change them between
           the transfers.

           The handle is the return code from a curl_easy_init(3)  or
           curl_easy_duphandle(3) call.

## BEHAVIOR OPTIONS

           CURLOPT_VERBOSE
               Set  the  parameter  to non-zero to get the library to
               display a lot of verbose information about its  opera-
               tions.  Very useful for libcurl and/or protocol debug-
               ging and understanding.

               You hardly ever want this set in production  use,  you
               will  almost  always  want  this when you debug/report
               problems. Another neat option  for  debugging  is  the
               CURLOPT_DEBUGFUNCTION.

           CURLOPT_HEADER
               A  non-zero parameter tells the library to include the
               data (like HTTP).

           CURLOPT_NOPROGRESS
               A non-zero parameter tells the library to shut of  the
               built-in progress meter completely.

               NOTE: future versions of libcurl is likely to not have
               any built-in progress meter at all.

           CURLOPT_NOSIGNAL
               Pass a long. If it is non-zero, libcurl will  not  use
               any  functions  that  install  signal  handlers or any
               functions that cause signals to be sent  to  the  pro-
               cess.  This  option  is  mainly  here  to allow multi-
               threaded unix applications to still set/use all  time-
               out  options  etc,  without  risking  getting signals.
               (Added in 7.10)

## CALLBACK OPTIONS

           CURLOPT_WRITEFUNCTION
               Function pointer that should match the following  pro-
               totype:  size_t  function(  void  *ptr,  size_t  size,
               size_t nmemb, void *stream); This function gets called
               by  libcurl  as  soon  as  there is data reveiced that
               needs to be saved. The size of the data pointed to  by
               ptr is size multiplied with nmemb, it will not be zero
               terminated. Return the number of bytes actually  taken
               care of. If that amount differs from the amount passed
               to your function, it'll signal an error to the library
               and   it   will   abort   the   transfer   and  return
               CURLE_WRITE_ERROR.

               Set the stream argument with the CURLOPT_FILE  option.

               NOTE:  you  will be passed as much data as possible in
               all invokes, but you cannot possibly make any  assump-
               tions.  It  may  be one byte, it may be thousands. The
               maximum amount of data that can be passed to the write
               callback   is  defined  in  the  curl.h  header  file:
               CURL_MAX_WRITE_SIZE.

           CURLOPT_WRITEDATA
               Data pointer to pass to the file write function.  Note
               that if you specify the CURLOPT_WRITEFUNCTION, this is
               the pointer you'll get as input. If you  don't  use  a
               callback,  you  must  pass  a 'FILE *' as libcurl will
               pass this to fwrite() when writing data.

               NOTE: If you're using libcurl as a win32 DLL, you MUST
               use  the  CURLOPT_WRITEFUNCTION if you set this option
               or you will experience crashes.
               LOPT_FILE,  the  name CURLOPT_WRITEDATA was introduced
               in 7.9.7.

           CURLOPT_READFUNCTION
               Function pointer that should match the following  pro-
               totype:  size_t  function(  void  *ptr,  size_t  size,
               size_t nmemb, void *stream); This function gets called
               by  libcurl  as soon as it needs to read data in order
               to send it to the peer. The data area  pointed  at  by
               the pointer ptr may be filled with at most size multi-
               plied with nmemb number of bytes. Your  function  must
               return  the  actual number of bytes that you stored in
               that memory area. Returning 0 will signal  end-of-file
               to the library and cause it to stop the current trans-
               fer.

           CURLOPT_READDATA
               Data pointer to pass to the file read  function.  Note
               that  if you specify the CURLOPT_READFUNCTION, this is
               the pointer you'll get as input. If you don't  specify
               a read callback, this must be a valid FILE *.

               NOTE: If you're using libcurl as a win32 DLL, you MUST
               use a CURLOPT_READFUNCTION if you set this option.

               This option is also known with  the  older  name  CUR-
               LOPT_INFILE,  the name CURLOPT_READDATA was introduced
               in 7.9.7.

           CURLOPT_PROGRESSFUNCTION
               Function    pointer    that    should    match     the
               curl_progress_callback      prototype     found     in
               <curl/curl.h>. This function gets  called  by  libcurl
               instead  of  its  internal  equivalent with a frequent
               interval during data transfer.   Unknown/unused  argu-
               ment  values  will  be  set  to zero (like if you only
               download data, the upload size will remain 0). Return-
               ing  a  non-zero  value  from this callback will cause
               libcurl   to   abort   the   transfer    and    return
               CURLE_ABORTED_BY_CALLBACK.

               Also note that CURLOPT_NOPROGRESS must be set to FALSE
               to make this function actually get called.

           CURLOPT_PROGRESSDATA
               Pass a pointer that will be untouched by  libcurl  and
               passed  as the first argument in the progress callback
               set with CURLOPT_PROGRESSFUNCTION.

           CURLOPT_PASSWDFUNCTION
               Pass a pointer to a curl_passwd_callback function that
               will  be called instead of the internal one if libcurl
               char* buffer, int buflen );.  If set to NULL, it  sets
               back  the function to the internal default one. If the
               function returns a non-zero value, it will  abort  the
               operation  and  an  error (CURLE_BAD_PASSWORD_ENTERED)
               will be returned.  client is a  generic  pointer,  see
               CURLOPT_PASSWDDATA.    prompt   is  a  zero-terminated
               string that is text that prefixes the  input  request.
               buffer is a pointer to data where the entered password
               should be stored and buflen is the maximum  number  of
               bytes  that  may  be written in the buffer.  (Added in
               7.4.2)

           CURLOPT_PASSWDDATA
               Pass a void * to whatever data you  want.  The  passed
               pointer  will  be  the  first  argument  sent  to  the
               specifed CURLOPT_PASSWDFUNCTION  function.  (Added  in
               7.4.2)

           CURLOPT_HEADERFUNCTION
               Function  pointer that should match the following pro-
               totype:  size_t  function(  void  *ptr,  size_t  size,
               size_t  nmemb,  void  *stream);.  This  function  gets
               called by libcurl as soon as there is received  header
               data  that  needs  to be written down. The headers are
               guaranteed to be written one-by-one and only  complete
               lines  are  written.  Parsing  headers  should be easy
               enough using this. The size of the data pointed to  by
               ptr  is size multiplied with nmemb.  The pointer named
               stream will be the one you passed to libcurl with  the
               CURLOPT_WRITEHEADER  option.   Return  the  number  of
               bytes actually written or return -1 to signal error to
               the  library  (it  will cause it to abort the transfer
               with  a  CURLE_WRITE_ERROR  return  code).  (Added  in
               7.7.2)

           CURLOPT_WRITEHEADER
               Pass  a pointer to be used to write the header part of
               the received data to. If you don't use your own  call-
               back to take care of the writing, this must be a valid
               FILE *. See  also  the  CURLOPT_HEADERFUNCTION  option
               above on how to set a custom get-all-headers callback.

           CURLOPT_DEBUGFUNCTION
               Function pointer that should match the following  pro-
               totype:  int  curl_debug_callback  (CURL *, curl_info-
               type, char *, size_t,  void  *);  This  function  will
               receive   debug   information  if  CURLOPT_VERBOSE  is
               enabled. The  curl_infotype  argument  specifies  what
               kind of information it is. This funtion must return 0.

               NOTE: the data pointed to by the char * passed to this
               function  WILL  NOT  be  zero  terminated, but will be
               Pass a pointer to whatever you want passed in to  your
               CURLOPT_DEBUGFUNCTION  in  the  last  void * argument.
               This pointer is not used by libcurl, it is only passed
               to the callback.

## ERROR OPTIONS

           CURLOPT_ERRORBUFFER
               Pass  a  char * to a buffer that the libcurl may store
               human readable error messages in.  This  may  be  more
               helpful  than  just  the return code from the library.
               The buffer must be at least CURL_ERROR_SIZE big.

               Use CURLOPT_VERBOSE and CURLOPT_DEBUGFUNCTION to  bet-
               ter debug/trace why errors happen.

               Note:  if  the  library  does not return an error, the
               buffer may not have been touched. Do not rely  on  the
               contents in those cases.

           CURLOPT_STDERR
               Pass  a FILE * as parameter. This is the stream to use
               instead of stderr internally when reporting errors.

           CURLOPT_FAILONERROR
               A  non-zero  parameter  tells  the  library  to   fail
               silently  if  the  HTTP  code  returned is equal to or
               larger than 300. The default action would be to return
               the page normally, ignoring that code.

## NETWORK OPTIONS

           CURLOPT_URL
               The actual URL to deal with. The parameter should be a
               char * to a zero terminated string.  The  string  must
               remain  present  until  curl no longer needs it, as it
               doesn't copy the string.

               NOTE: this option is (the only one) required to be set
               before curl_easy_perform(3) is called.

           CURLOPT_PROXY
               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 CURLOPT_PROXYPORT.

               NOTE: when you tell the library to use a  HTTP  proxy,
               impact  on  what other features of the library you can
               use, such as CURLOPT_QUOTE and similar  FTP  specifics
               that  don't  work  unless  you tunnel through the HTTP
               proxy. Such tunneling is activated with  CURLOPT_HTTP-
               PROXYTUNNEL.

               NOTE2:  libcurl  respects  the  environment  variables
               http_proxy, ftp_proxy, all_proxy etc, if any of  those
               is set.

           CURLOPT_PROXYPORT
               Pass  a long with this option to set the proxy port to
               connect to unless it is specified in the proxy  string
               CURLOPT_PROXY.

           CURLOPT_PROXYTYPE
               Pass a long with this option to set type of the proxy.
               Available options  for  this  are  CURLPROXY_HTTP  and
               CURLPROXY_SOCKS5,  with  the  HTTP  one being default.
               (Added in 7.10)

           CURLOPT_HTTPPROXYTUNNEL
               Set the parameter to non-zero to get  the  library  to
               tunnel all operations through a given HTTP proxy. Note
               that 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.
               (Added in 7.3)

           CURLOPT_INTERFACE
               Pass  a  char  *  as parameter. This set the interface
               name to use as outgoing network  interface.  The  name
               can  be  an  interface  name,  an IP address or a host
               name. (Added in 7.3)

           CURLOPT_DNS_CACHE_TIMEOUT
               Pass a long, this sets the timeout  in  seconds.  Name
               resolves  will  be  kept  in memory for this number of
               seconds.  Set  to  zero  (0)  to  completely   disable
               caching,  or  set  to  -1  to  make the cached entries
               remain forever. By default, libcurl caches info for 60
               seconds. (Added in 7.9.3)

           CURLOPT_DNS_USE_GLOBAL_CACHE
               Pass  a  long. If the value is non-zero, 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 varible. (Added
               in 7.9.3)

           CURLOPT_BUFFERSIZE
               Pass  a  long  specifying  your  prefered size for the
               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)

## NAMES and PASSWORDS OPTIONS

           CURLOPT_NETRC
               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.

               Note:  libcurl  uses  a  user  name  (and  supplied or
               prompted password) supplied  with  CURLOPT_USERPWD  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
                    information in the URL is to be  preferred.   The
                    file  will be scanned with the host and user name
                    (to find the password  only)  or  with  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
                    information 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 with the host only.

           Only machine name, user name and password are taken into
               account
               (init macros and similar things aren't supported).

               Note: 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_USERPWD
               Pass a char * as  parameter,  which  should  be  [user
               CURLOPT_PASSWDFUNCTION  can  be  used  to set your own
               prompt function.

           CURLOPT_PROXYUSERPWD
               Pass a char * as  parameter,  which  should  be  [user
               name]:[password] to use for the connection to the HTTP
               proxy. If the  password  is  left  out,  you  will  be
               prompted for it. CURLOPT_PASSWDFUNCTION can be used to
               set your own prompt function.

## HTTP OPTIONS

           CURLOPT_ENCODING
               Two encodings are supported dentity, which does  noth-
               ing, and deflate to request the server to compress its
               reponse using the  zlib  algorithm.  This  is  not  an
               order,  the server may or may not do it.  See the spe-
               cial file lib/README.encoding for details.

           CURLOPT_FOLLOWLOCATION
               A non-zero parameter tells the library to  follow  any
               Location:  header  that  the server sends as part of a
               HTTP header.

               NOTE: this means that the  library  will  re-send  the
               same  request on the new location and follow new Loca-
               tion: headers all the way until no more  such  headers
               are  returned.  CURLOPT_MAXREDIRS can be used to limit
               the number of redirects libcurl will follow.

           CURLOPT_MAXREDIRS
               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  is  used  at  the
               same time. (Added in 7.5)

           CURLOPT_PUT
               A non-zero parameter tells the library to use HTTP PUT
               to transfer data. The data should  be  set  with  CUR-
               LOPT_READDATA and CURLOPT_INFILESIZE.

           CURLOPT_POST
               A non-zero parameter tells the library to do a regular
               HTTP post. This is  a  normal  application/x-www-form-
               urlencoded  kind,  which is the most commonly used one
               by HTML forms. See the CURLOPT_POSTFIELDS  option  for
               how to specify the data to post and CURLOPT_POSTFIELD-
               SIZE in how  to  set  the  data  size.  Starting  with
               libcurl  7.8,  this option is obsolete. Using the CUR-
               LOPT_POSTFIELDS option will imply this option.
               Pass a char * as parameter, which should be  the  full
               data  to post in a HTTP post operation. This is a nor-
               mal application/x-www-form-urlencoded kind,  which  is
               the most commonly used one by HTML forms. See also the
               CURLOPT_POST.  Since  7.8,  using   CURLOPT_POSTFIELDS
               implies CURLOPT_POST.

               Note:    to   make   multipart/formdata   posts   (aka
               rfc1867-posts), check out the CURLOPT_HTTPPOST option.

           CURLOPT_POSTFIELDSIZE
               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 zero, the library will
               use strlen() to get the size. (Added in libcurl 7.2)

           CURLOPT_HTTPPOST
               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  HTTP
               post  structs as parameter.  The linked list should be
               a fully valid list of 'struct HttpPost' structs  prop-
               erly  filled  in.  The best and most elegant way to do
               this, 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).

           CURLOPT_REFERER
               Pass a pointer to a zero terminated string as  parame-
               ter. 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.

           CURLOPT_USERAGENT
               Pass a pointer to a zero terminated string as  parame-
               ter.  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_HTTPHEADER.

           CURLOPT_HTTPHEADER
               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 other-
               wise generated and used by  libcurl  internally,  your
               added  one  will  be used instead. If you add a header
               get disabled. Thus, using this option you can add  new
               headers,  replace internal headers and remove internal
               headers. 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.

               NOTE:The most commonly replaced headers  have  "short-
               cuts" in the options CURLOPT_COOKIE, CURLOPT_USERAGENT
               and CURLOPT_REFERER.

           CURLOPT_HTTP200ALIASES
               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 exam-
               ple,  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.

               NOTE:The  alias  itself  is not parsed for any version
               strings.  So if your alias  is  "MYHTTP/9.9",  Libcurl
               will not treat the server as responding with HTTP ver-
               sion 9.9.  Instead Libcurl will use the value  set  by
               option CURLOPT_HTTP_VERSION.

           CURLOPT_COOKIE
               Pass  a pointer to a zero terminated string as parame-
               ter. It will be used to  set  a  cookie  in  the  http
               request.  The format of the string should be NAME=CON-
               TENTS, where NAME is the cookie name and  CONTENTS  is
               what the cookie should contain.

               If  you  need to set mulitple cookies, you need to set
               them all using a single option and thus  you  need  to
               concat  them  all  in  one single string. Set multiple
               cookies in  one  string  like  this:  "name1=content1;
               name2=content2;" etc.

               Using  this  option  multiple times will only make the
               latest string override the previously ones.

           CURLOPT_COOKIEFILE
               Pass a pointer to a zero terminated string as  parame-
               ter.  It  should contain the name of your file holding
               cookie data  to  read.  The  cookie  data  may  be  in

               Given an empty or non-existing file, this option  will
               enable  cookies for this curl handle, making it under-
               stand and parse received cookies and then use matching
               cookies in future request.

           CURLOPT_COOKIEJAR
               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  ses-
               sion,  so if you for example follow a location it will
               make matching cookies get sent accordingly. (Added  in
               7.9)

           CURLOPT_TIMECONDITION
               Pass  a  long  as parameter. This defines how the CUR-
               LOPT_TIMEVALUE time value is treated. You can set this
               parameter  to  TIMECOND_IFMODSINCE  or  TIMECOND_IFUN-
               MODSINCE. This is a HTTP-only feature. (TBD)

           CURLOPT_TIMEVALUE
               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.

           CURLOPT_HTTPGET
               Pass a long. If the long is non-zero, this forces  the
               HTTP request to get back to GET. Only really usable if
               POST, PUT or a custom request have  been  used  previ-
               ously using the same curl handle. (Added in 7.8.1)

           CURLOPT_HTTP_VERSION
               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 rea-
               son.

               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.

## FTP OPTIONS

               Pass  a pointer to a zero terminated string as parame-
               ter. It will be used to get the IP address to use  for
               the  ftp  PORT instruction. 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, an network interface name (under Unix) or just a
               '-' letter to let the library use your systems default
               IP address. Default FTP operations  are  passive,  and
               thus won't use PORT.

           CURLOPT_QUOTE
               Pass  a  pointer  to  a linked list of FTP commands to
               pass to the server prior to  your  ftp  request.  This
               will  be done before any other FTP commands are issued
               (even before the CWD command). The linked list  should
               be  a fully valid list of 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.

           CURLOPT_POSTQUOTE
               Pass a pointer to a linked list  of  FTP  commands  to
               pass  to  the  server after your ftp transfer request.
               The linked list should be a fully valid list of struct
               curl_slist structs properly filled in as described for
               CURLOPT_QUOTE. Disable this operation again by setting
               a NULL to this option.

           CURLOPT_PREQUOTE
               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. Disable this operation again by setting
               a NULL to this option.

           CURLOPT_FTPLISTONLY
               A non-zero parameter tells the library  to  just  list
               the names of an ftp directory, instead of doing a full
               directory listing that would include file sizes, dates
               etc.

               This  causes  an  FTP NLST command to be sent.  Beware
               that  some  FTP  servers  list  only  files  in  their
               response  to  NLST; they might not include subdirecto-
               ries and symbolic links.

           CURLOPT_FTPAPPEND
               A non-zero parameter tells the library  to  append  to
               the  remote file instead of overwrite it. This is only
               useful when uploading to a ftp site.

               Pass a long. If the value is non-zero, it  tells  curl
               to  use  the EPSV command when doing passive FTP down-
               loads (which it always does by  default).  Using  EPSV
               means  that  it  will first attempt to use EPSV before
               using PASV, but if  you  pass  FALSE  (zero)  to  this
               option, it will not try using EPSV, only plain PASV.

## PROTOCOL OPTIONS

           CURLOPT_TRANSFERTEXT
               A  non-zero  parameter  tells the library to use ASCII
               mode for ftp transfers, instead of the default  binary
               transfer. For LDAP transfers it gets the data in plain
               text instead of HTML and 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 similar.

           CURLOPT_CRLF
               Convert Unix newlines to CRLF newlines on transfers.

           CURLOPT_RANGE
               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 multiple intervals
               will  cause the HTTP server to send the response docu-
               ment in pieces (using standard MIME  separation  tech-
               niques).

           CURLOPT_RESUME_FROM
               Pass  a  long  as parameter. It contains the offset in
               number of bytes that you want the  transfer  to  start
               from.

           CURLOPT_CUSTOMREQUEST
               Pass  a pointer to a zero terminated string as parame-
               ter. It will be user instead of GET or HEAD when doing
               the  HTTP  request. 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 com-
               mand first.

           CURLOPT_FILETIME
               Pass a long. If it is a non-zero value,  libcurl  will
               attempt  to  get  the  modification 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

           CURLOPT_NOBODY
               A  non-zero parameter 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.

           CURLOPT_INFILESIZE
               When  uploading  a  file to a remote site, this option
               should be used to tell libcurl what the expected  size
               of the infile is.

           CURLOPT_UPLOAD
               A  non-zero parameter tells the library to prepare for
               an upload. The CURLOPT_READDATA and CURLOPT_INFILESIZE
               are also interesting for uploads.

## CONNECTION OPTIONS

           CURLOPT_TIMEOUT
               Pass  a  long as parameter containing the maximum time
               in seconds that you allow the libcurl transfer  opera-
               tion  to  take. Normally, name lookups can take a con-
               siderable time and limiting operations 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.

               NOTE:  this  is  not recommended to use in unix multi-
               threaded programs, as  it  uses  signals  unless  CUR-
               LOPT_NOSIGNAL (see above) is set.

           CURLOPT_LOW_SPEED_LIMIT
               Pass  a  long  as  parameter. It contains the transfer
               speed in bytes per second that the transfer should  be
               below  during  CURLOPT_LOW_SPEED_TIME  seconds for the
               library to consider it too slow and abort.

           CURLOPT_LOW_SPEED_TIME
               Pass a long as parameter. It contains the time in sec-
               onds  that  the  transfer  should  be  below  the CUR-
               LOPT_LOW_SPEED_LIMIT for the library  to  consider  it
               too slow and abort.

           CURLOPT_MAXCONNECTS
               Pass  a  long.  The  set number will be the persistent
               connection cache size. The set amount will be the max-
               imum  amount  of  simultaneously open connections that
               libcurl may cache. Default is 5, and there isn't  much
               point  in changing this value unless you are perfectly
               aware  of  how  this  work   and   changes   libcurl's
               behaviour.  This  concerns connection using any of the
               protocols that support persistent connections.
               LOPT_CLOSEPOLICY  to  figure out which of the existing
               connections to close to prevent  the  number  of  open
               connections to increase.

               NOTE:  if  you  already  have performed transfers with
               this curl handle, setting a smaller  MAXCONNECTS  than
               before may cause open connections to get closed unnec-
               essarily. (Added in 7.7)

           CURLOPT_CLOSEPOLICY
               Pass a long. This  option  sets  what  policy  libcurl
               should use when the connection cache is filled and one
               of the open connections has to be closed to make  room
               for  a  new  connection. This must be one of the CURL-
               CLOSEPOLICY_*     defines.      Use      CURLCLOSEPOL-
               ICY_LEAST_RECENTLY_USED to make libcurl close the con-
               nection that was least recently used, that  connection
               is  also  least  likely  to  be capable of re-use. Use
               CURLCLOSEPOLICY_OLDEST to make libcurl close the  old-
               est  connection,  the one that was created first among
               the ones in the  connection  cache.  The  other  close
               policies are not support yet. (Added in 7.7)

           CURLOPT_FRESH_CONNECT
               Pass a long. Set to non-zero to make the next transfer
               use a new (fresh) connection by force. If the  connec-
               tion  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).  (Added  in
               7.7)

           CURLOPT_FORBID_REUSE
               Pass a long. Set to non-zero to make the next transfer
               explicitly close the connection when  done.  Normally,
               libcurl  keep all connections alive when done with one
               transfer in case there comes a succeeding one 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 possibly
               later re-use (default behavior). (Added in 7.7)

           CURLOPT_CONNECTTIMEOUT
               Pass a long. It should contain  the  maximum  time  in
               seconds that you allow the connection to the server to
               take.  This only limits 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 option.
               threaded  programs,  as  it  uses  signals unless CUR-
               LOPT_NOSIGNAL (see above) is set.

## SSL and SECURITY OPTIONS

           CURLOPT_SSLCERT
               Pass a pointer to a zero terminated string as  parame-
               ter.  The  string should be the file name of your cer-
               tificate. The default  format  is  "PEM"  and  can  be
               changed with CURLOPT_SSLCERTTYPE.

           CURLOPT_SSLCERTTYPE
               Pass  a pointer to a zero terminated string as parame-
               ter. The string should be the format of your  certifi-
               cate.  Supported  formats are "PEM" and "DER".  (Added
               in 7.9.3)

           CURLOPT_SSLCERTPASSWD
               Pass a pointer to a zero terminated string as  parame-
               ter.  It  will be used as the password required to use
               the CURLOPT_SSLCERT certificate. If  the  password  is
               not  supplied,  you  will  be  prompted  for  it. CUR-
               LOPT_PASSWDFUNCTION can be used to set your own prompt
               function.

               NOTE:This  option  is replaced by CURLOPT_SSLKEYPASSWD
               and only cept for backward  compatibility.  You  never
               needed  a  pass  phrase  to load a certificate but you
               need one to load your private key.

           CURLOPT_SSLKEY
               Pass a pointer to a zero terminated string as  parame-
               ter.  The  string should be the file name of your pri-
               vate key. The default  format  is  "PEM"  and  can  be
               changed with CURLOPT_SSLKEYTYPE. (Added in 7.9.3)

           CURLOPT_SSLKEYTYPE
               Pass  a pointer to a zero terminated string as parame-
               ter. The string should be the format of  your  private
               key.  Supported  formats  are  "PEM", "DER" and "ENG".
               (Added in 7.9.3)

               NOTE:The format "ENG" enables you to load the  private
               key  from a crypto engine. in this case CURLOPT_SSLKEY
               is used as an identifier passed  to  the  engine.  You
               have to set the crypto engine with CURLOPT_SSL_ENGINE.

           CURLOPT_SSLKEYPASSWD
               Pass a pointer to a zero terminated string as  parame-
               ter.  It  will be used as the password required to use
               the CURLOPT_SSLKEY private key. If the password is not
               supplied, you will be prompted for it. CURLOPT_PASSWD-

           CURLOPT_SSL_ENGINE
               Pass  a pointer to a zero terminated string as parame-
               ter. It will be used as the identifier for the  crypto
               engine you want to use for your private key. (Added in
               7.9.3)

               NOTE:If  the   crypto   device   cannot   be   loaded,
               CURLE_SSL_ENGINE_NOTFOUND is returned.

           CURLOPT_SSL_ENGINEDEFAULT
               Sets the actual crypto engine as the default for (asy-
               metric) crypto operations. (Added in 7.9.3)

               NOTE:If   the   crypto   device   cannot    be    set,
               CURLE_SSL_ENGINE_SETFAILED is returned.

           CURLOPT_SSLVERSION
               Pass  a  long as parameter. Set what version of SSL to
               attempt to use, 2 or 3. By default,  the  SSL  library
               will try to solve this by itself although some servers
               make this difficult why you at times may have  to  use
               this option.

           CURLOPT_SSL_VERIFYPEER
               Pass  a  long that is set to a zero value to stop curl
               from verifying the peer's certificate  (7.10  starting
               setting  this  option  to TRUE by default).  Alternate
               certificates to verify against can be  specified  with
               the  CURLOPT_CAINFO  option (Added in 7.4.2) or a cer-
               tificate directory can  be  specified  with  the  CUR-
               LOPT_CAPATH option (Added in 7.9.8).  As of 7.10, curl
               installs a default bundle.  CURLOPT_SSL_VERIFYHOST may
               also  need  to  be  set to 1 or 0 if CURLOPT_SSL_VERI-
               FYPEER is disabled (it defaults to 2).

           CURLOPT_CAINFO
               Pass a char * to a zero  terminated  string  naming  a
               file  holding  one  or more certificates to verify the
               peer with. This only makes sense when used in combina-
               tion with the CURLOPT_SSL_VERIFYPEER option. (Added in
               7.4.2)

           CURLOPT_CAPATH
               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  pre-
               pared  using  the  openssl c_rehash utility. This only
               makes sense when used in  combination  with  the  CUR-
               LOPT_SSL_VERIFYPEER option. The CAPATH function appar-
               ently does not work in Windows due to some  limitation
               in openssl. (Added in 7.9.8)
               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
               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
               Pass a long. Set if we should verify the  Common  name
               from  the peer certificate in the SSL handshake, set 1
               to check existence, 2 to ensure that  it  matches  the
               provided hostname. This is by default set to 2. (Added
               in 7.8.1, default changed in 7.10)

           CURLOPT_SSL_CIPHER_LIST
               Pass a char *, pointing to a  zero  terminated  string
               holding the list of ciphers to use for the SSL connec-
               tion. The list must be syntactly correct, it  consists
               of  one  or  more  cipher strings separated by colons.
               Commas or spaces are also  acceptable  separators  but
               colons  are  normally  used,  , - and + can be used as
               operators. 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

           CURLOPT_KRB4LEVEL
               Pass a char * as  parameter.  Set  the  krb4  security
               level,  this  also  enables krb4 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 dis-
               able  kerberos4.  The  kerberos support only works for
               FTP. (Added in 7.3)

## OTHER OPTIONS

           CURLOPT_PRIVATE
               Pass a char * as  parameter,  pointing  to  data  that
               should  be  associated  with  the  curl  handle.   The
               pointer  can  be  subsequently  retrieved  using   the
               CURLINFO_PRIVATE  options to curl_easy_getinfo. (Added
               in 7.10.3)

## RETURN VALUE

           CURLE_OK (zero) means that the option  was  set  properly,
           descriptions.

## SEE ALSO

           curl_easy_init(3), curl_easy_cleanup(3),

## BUGS

           If you find any bugs, or just have questions, subscribe to
           one of the mailing lists and post. We won't bite.