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      You always find news about what's going on as well as the latest versions
      from the curl web pages, located at:
    
    
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            http://curl.haxx.se
    
    
    SIMPLE USAGE
    
      Get the main page from netscape's web-server:
    
            curl http://www.netscape.com/
    
      Get the root README file from funet's ftp-server:
    
            curl ftp://ftp.funet.fi/README
    
      Get a web page from a server using port 8000:
    
            curl http://www.weirdserver.com:8000/
    
      Get a list of the root directory of an FTP site:
    
    
            curl ftp://cool.haxx.se/
    
      Get a gopher document from funet's gopher server:
    
            curl gopher://gopher.funet.fi
    
    
      Get the definition of curl from a dictionary:
    
            curl dict://dict.org/m:curl
    
    
      Fetch two documents at once:
    
            curl ftp://cool.haxx.se/ http://www.weirdserver.com:8000/
    
    
    DOWNLOAD TO A FILE
    
      Get a web page and store in a local file:
    
            curl -o thatpage.html http://www.netscape.com/
    
      Get a web page and store in a local file, make the local file get the name
      of the remote document (if no file name part is specified in the URL, this
      will fail):
    
            curl -O http://www.netscape.com/index.html
    
    
      Fetch two files and store them with their remote names:
    
            curl -O www.haxx.se/index.html -O curl.haxx.se/download.html
    
    
    USING PASSWORDS
    
     FTP
    
       To ftp files using name+passwd, include them in the URL like:
    
            curl ftp://name:passwd@machine.domain:port/full/path/to/file
    
       or specify them with the -u flag like
    
            curl -u name:passwd ftp://machine.domain:port/full/path/to/file
    
     HTTP
    
       The HTTP URL doesn't support user and password in the URL string. Curl
       does support that anyway to provide a ftp-style interface and thus you can
       pick a file like:
    
            curl http://name:passwd@machine.domain/full/path/to/file
    
       or specify user and password separately like in
    
            curl -u name:passwd http://machine.domain/full/path/to/file
    
       NOTE! Since HTTP URLs don't support user and password, you can't use that
       style when using Curl via a proxy. You _must_ use the -u style fetch
       during such circumstances.
    
     HTTPS
    
       Probably most commonly used with private certificates, as explained below.
    
     GOPHER
    
       Curl features no password support for gopher.
    
    PROXY
    
     Get an ftp file using a proxy named my-proxy that uses port 888:
    
            curl -x my-proxy:888 ftp://ftp.leachsite.com/README
    
     Get a file from a HTTP server that requires user and password, using the
     same proxy as above:
    
            curl -u user:passwd -x my-proxy:888 http://www.get.this/
    
     Some proxies require special authentication. Specify by using -U as above:
    
            curl -U user:passwd -x my-proxy:888 http://www.get.this/
    
     See also the environment variables Curl support that offer further proxy
     control.
    
    RANGES
    
      With HTTP 1.1 byte-ranges were introduced. Using this, a client can request
      to get only one or more subparts of a specified document. Curl supports
      this with the -r flag.
    
      Get the first 100 bytes of a document:
    
            curl -r 0-99 http://www.get.this/
    
      Get the last 500 bytes of a document:
    
            curl -r -500 http://www.get.this/
    
      Curl also supports simple ranges for FTP files as well. Then you can only
      specify start and stop position.
    
      Get the first 100 bytes of a document using FTP:
    
            curl -r 0-99 ftp://www.get.this/README  
    
    UPLOADING
    
     FTP
    
      Upload all data on stdin to a specified ftp site:
    
    
            curl -T - ftp://ftp.upload.com/myfile
    
    
      Upload data from a specified file, login with user and password:
    
            curl -T uploadfile -u user:passwd ftp://ftp.upload.com/myfile
    
      Upload a local file to the remote site, and use the local file name remote
      too:
     
            curl -T uploadfile -u user:passwd ftp://ftp.upload.com/
    
      Upload a local file to get appended to the remote file using ftp:
    
            curl -T localfile -a ftp://ftp.upload.com/remotefile
    
    
      Curl also supports ftp upload through a proxy, but only if the proxy is
      configured to allow that kind of tunneling. If it does, you can run curl in
      a fashion similar to:
    
            curl --proxytunnel -x proxy:port -T localfile ftp.upload.com
    
    
     HTTP
    
      Upload all data on stdin to a specified http site:
    
    
            curl -T - http://www.upload.com/myfile
    
    
      Note that the http server must've been configured to accept PUT before this
      can be done successfully.
    
      For other ways to do http data upload, see the POST section below.
    
    VERBOSE / DEBUG
    
      If curl fails where it isn't supposed to, if the servers don't let you
      in, if you can't understand the responses: use the -v flag to get VERBOSE
      fetching. Curl will output lots of info and all data it sends and
      receives in order to let the user see all client-server interaction.
    
            curl -v ftp://ftp.upload.com/
    
    DETAILED INFORMATION
    
      Different protocols provide different ways of getting detailed information
      about specific files/documents. To get curl to show detailed information
      about a single file, you should use -I/--head option. It displays all
      available info on a single file for HTTP and FTP. The HTTP information is a
      lot more extensive.
    
      For HTTP, you can get the header information (the same as -I would show)
      shown before the data by using -i/--include. Curl understands the
      -D/--dump-header option when getting files from both FTP and HTTP, and it
      will then store the headers in the specified file.
    
    
      Store the HTTP headers in a separate file (headers.txt in the example):
    
    Daniel Stenberg's avatar
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            curl --dump-header headers.txt curl.haxx.se
    
    
      Note that headers stored in a separate file can be very useful at a later
      time if you want curl to use cookies sent by the server. More about that in
      the cookies section.
    
    POST (HTTP)
    
      It's easy to post data using curl. This is done using the -d <data>
      option.  The post data must be urlencoded.
    
      Post a simple "name" and "phone" guestbook.
    
            curl -d "name=Rafael%20Sagula&phone=3320780" \
                    http://www.where.com/guest.cgi
    
      How to post a form with curl, lesson #1:
    
      Dig out all the <input> tags in the form that you want to fill in. (There's
      a perl program called formfind.pl on the curl site that helps with this).
    
      If there's a "normal" post, you use -d to post. -d takes a full "post
      string", which is in the format
    
            <variable1>=<data1>&<variable2>=<data2>&...
    
      The 'variable' names are the names set with "name=" in the <input> tags, and
      the data is the contents you want to fill in for the inputs. The data *must*
      be properly URL encoded. That means you replace space with + and that you
      write weird letters with %XX where XX is the hexadecimal representation of
      the letter's ASCII code.
    
      Example:
    
      (page located at http://www.formpost.com/getthis/
    
            <form action="post.cgi" method="post">
            <input name=user size=10>
            <input name=pass type=password size=10>
            <input name=id type=hidden value="blablabla">
            <input name=ding value="submit">
            </form>
    
      We want to enter user 'foobar' with password '12345'.
    
      To post to this, you enter a curl command line like:
    
            curl -d "user=foobar&pass=12345&id=blablabla&dig=submit"  (continues)
              http://www.formpost.com/getthis/post.cgi
    
    
      While -d uses the application/x-www-form-urlencoded mime-type, generally
      understood by CGI's and similar, curl also supports the more capable
      multipart/form-data type. This latter type supports things like file upload.
    
      -F accepts parameters like -F "name=contents". If you want the contents to
      be read from a file, use <@filename> as contents. When specifying a file,
    
      you can also specify the file content type by appending ';type=<mime type>'
      to the file name. You can also post the contents of several files in one field.
      For example, the field name 'coolfiles' is used to send three  files, with
      different content types using the following syntax:
    
    
            curl -F "coolfiles=@fil1.gif;type=image/gif,fil2.txt,fil3.html" \
            http://www.post.com/postit.cgi
    
    
      If the content-type is not specified, curl will try to guess from the file
      extension  (it only knows a few), or use the previously specified type
      (from an earlier file if several files are specified in a list) or else it
      will  using the default type 'text/plain'.
    
    
      Emulate a fill-in form with -F. Let's say you fill in three fields in a
      form. One field is a file name which to post, one field is your name and one
      field is a file description. We want to post the file we have written named
      "cooltext.txt". To let curl do the posting of this data instead of your
    
      favourite browser, you have to read the HTML source of the form page and find
      the names of the input fields. In our example, the input field names are
    
      'file', 'yourname' and 'filedescription'.
    
            curl -F "file=@cooltext.txt" -F "yourname=Daniel" \
                 -F "filedescription=Cool text file with cool text inside" \
                 http://www.post.com/postit.cgi
    
    
      To send two files in one post you can do it in two ways:
    
    
      1. Send multiple files in a single "field" with a single field name:
     
            curl -F "pictures=@dog.gif,cat.gif" 
     
      2. Send two fields with two field names: 
    
            curl -F "docpicture=@dog.gif" -F "catpicture=@cat.gif" 
    
    
    
      A HTTP request has the option to include information about which address
    
      that referred to actual page.  Curl allows you to specify the
      referrer to be used on the command line. It is especially useful to
    
      fool or trick stupid servers or CGI scripts that rely on that information
      being available or contain certain data.
    
            curl -e www.coolsite.com http://www.showme.com/
    
    
      NOTE: The referer field is defined in the HTTP spec to be a full URL.
    
    
    USER AGENT
    
      A HTTP request has the option to include information about the browser
      that generated the request. Curl allows it to be specified on the command
      line. It is especially useful to fool or trick stupid servers or CGI
      scripts that only accept certain browsers.
    
      Example:
    
      curl -A 'Mozilla/3.0 (Win95; I)' http://www.nationsbank.com/
    
      Other common strings:
        'Mozilla/3.0 (Win95; I)'     Netscape Version 3 for Windows 95
        'Mozilla/3.04 (Win95; U)'    Netscape Version 3 for Windows 95
        'Mozilla/2.02 (OS/2; U)'     Netscape Version 2 for OS/2
        'Mozilla/4.04 [en] (X11; U; AIX 4.2; Nav)'           NS for AIX
        'Mozilla/4.05 [en] (X11; U; Linux 2.0.32 i586)'      NS for Linux
    
      Note that Internet Explorer tries hard to be compatible in every way:
        'Mozilla/4.0 (compatible; MSIE 4.01; Windows 95)'    MSIE for W95
    
      Mozilla is not the only possible User-Agent name:
        'Konqueror/1.0'             KDE File Manager desktop client
        'Lynx/2.7.1 libwww-FM/2.14' Lynx command line browser
    
    COOKIES
    
      Cookies are generally used by web servers to keep state information at the
      client's side. The server sets cookies by sending a response line in the
      headers that looks like 'Set-Cookie: <data>' where the data part then
      typically contains a set of NAME=VALUE pairs (separated by semicolons ';'
      like "NAME1=VALUE1; NAME2=VALUE2;"). The server can also specify for what
      path the "cookie" should be used for (by specifying "path=value"), when the
      cookie should expire ("expire=DATE"), for what domain to use it
      ("domain=NAME") and if it should be used on secure connections only
      ("secure").
    
      If you've received a page from a server that contains a header like:
            Set-Cookie: sessionid=boo123; path="/foo";
    
      it means the server wants that first pair passed on when we get anything in
      a path beginning with "/foo".
    
      Example, get a page that wants my name passed in a cookie:
    
            curl -b "name=Daniel" www.sillypage.com
    
      Curl also has the ability to use previously received cookies in following
      sessions. If you get cookies from a server and store them in a file in a
      manner similar to:
    
            curl --dump-header headers www.example.com
    
      ... you can then in a second connect to that (or another) site, use the
      cookies from the 'headers' file like:
    
            curl -b headers www.example.com
    
      Note that by specifying -b you enable the "cookie awareness" and with -L
      you can make curl follow a location: (which often is used in combination
      with cookies). So that if a site sends cookies and a location, you can
    
      use a non-existing file to trigger the cookie awareness like:
    
            curl -L -b empty.txt www.example.com
    
    
      The file to read cookies from must be formatted using plain HTTP headers OR
      as netscape's cookie file. Curl will determine what kind it is based on the
    
      file contents.  In the above command, curl will parse the header and store
      the cookies received from www.example.com.  curl will send to the server the
      stored cookies which match the request as it follows the location.  The
      file "empty.txt" may be a non-existant file.
      
    
    
    PROGRESS METER
    
      The progress meter exists to show a user that something actually is
      happening. The different fields in the output have the following meaning:
    
      % Total    % Received % Xferd  Average Speed          Time             Curr.
                                     Dload  Upload Total    Current  Left    Speed
      0  151M    0 38608    0     0   9406      0  4:41:43  0:00:04  4:41:39  9287
    
      From left-to-right:
       %             - percentage completed of the whole transfer
       Total         - total size of the whole expected transfer
       %             - percentage completed of the download
       Received      - currently downloaded amount of bytes
       %             - percentage completed of the upload
       Xferd         - currently uploaded amount of bytes
       Average Speed
       Dload         - the average transfer speed of the download
       Average Speed
       Upload        - the average transfer speed of the upload
       Time Total    - expected time to complete the operation
       Time Current  - time passed since the invoke
       Time Left     - expected time left to completetion
       Curr.Speed    - the average transfer speed the last 5 seconds (the first
                       5 seconds of a transfer is based on less time of course.)
    
      The -# option will display a totally different progress bar that doesn't
      need much explanation!
    
    SPEED LIMIT
    
    
      Curl allows the user to set the transfer speed conditions that must be met
      to let the transfer keep going. By using the switch -y and -Y you
      can make curl abort transfers if the transfer speed is below the specified
      lowest limit for a specified time.
    
      To have curl abort the download if the speed is slower than 3000 bytes per
    
      second for 1 minute, run:
    
            curl -y 3000 -Y 60 www.far-away-site.com
    
      This can very well be used in combination with the overall time limit, so
      that the above operatioin must be completed in whole within 30 minutes:
    
            curl -m 1800 -y 3000 -Y 60 www.far-away-site.com
    
    CONFIG FILE
    
      Curl automatically tries to read the .curlrc file (or _curlrc file on win32
    
      systems) from the user's home dir on startup.
    
      The config file could be made up with normal command line switches, but you
      can also specify the long options without the dashes to make it more
      readable. You can separate the options and the parameter with spaces, or
      with = or :. Comments can be used within the file. If the first letter on a
      line is a '#'-letter the rest of the line is treated as a comment.
    
      If you want the parameter to contain spaces, you must inclose the entire
      parameter within double quotes ("). Within those quotes, you specify a
      quote as \".
    
      NOTE: You must specify options and their arguments on the same line.
    
    
      Example, set default time out and proxy in a config file:
    
            # We want a 30 minute timeout:
            -m 1800
            # ... and we use a proxy for all accesses:
    
            proxy = proxy.our.domain.com:8080
    
    
      White spaces ARE significant at the end of lines, but all white spaces
      leading up to the first characters of each line are ignored.
    
      Prevent curl from reading the default file by using -q as the first command
      line parameter, like:
    
            curl -q www.thatsite.com
    
      Force curl to get and display a local help page in case it is invoked
      without URL by making a config file similar to:
    
            # default url to get
    
            url = "http://help.with.curl.com/curlhelp.html"
    
    
      You can specify another config file to be read by using the -K/--config
      flag. If you set config file name to "-" it'll read the config from stdin,
      which can be handy if you want to hide options from being visible in process
      tables etc:
    
    
            echo "user = user:passwd" | curl -K - http://that.secret.site.com
    
    
    EXTRA HEADERS
    
      When using curl in your own very special programs, you may end up needing
      to pass on your own custom headers when getting a web page. You can do
      this by using the -H flag.
    
      Example, send the header "X-you-and-me: yes" to the server when getting a
      page:
    
            curl -H "X-you-and-me: yes" www.love.com
    
    
      This can also be useful in case you want curl to send a different text in a
      header than it normally does. The -H header you specify then replaces the
      header curl would normally send. If you replace an internal header with an
      empty one, you prevent that header from being sent. To prevent the Host:
      header from being used:
    
            curl -H "Host:" www.server.com
    
    
    FTP and PATH NAMES
    
      Do note that when getting files with the ftp:// URL, the given path is
      relative the directory you enter. To get the file 'README' from your home
      directory at your ftp site, do:
    
            curl ftp://user:passwd@my.site.com/README
    
      But if you want the README file from the root directory of that very same
      site, you need to specify the absolute file name:
    
            curl ftp://user:passwd@my.site.com//README
    
      (I.e with an extra slash in front of the file name.)
    
    FTP and firewalls
    
      The FTP protocol requires one of the involved parties to open a second
      connction as soon as data is about to get transfered. There are two ways to
      do this.
    
      The default way for curl is to issue the PASV command which causes the
      server to open another port and await another connection performed by the
      client. This is good if the client is behind a firewall that don't allow
      incoming connections.
    
            curl ftp.download.com
    
      If the server for example, is behind a firewall that don't allow connections
      on other ports than 21 (or if it just doesn't support the PASV command), the
      other way to do it is to use the PORT command and instruct the server to
      connect to the client on the given (as parameters to the PORT command) IP
      number and port.
    
    
      The -P flag to curl supports a few different options. Your machine may have
    
      several IP-addresses and/or network interfaces and curl allows you to select
      which of them to use. Default address can also be used:
    
            curl -P - ftp.download.com
    
    
      Download with PORT but use the IP address of our 'le0' interface (this does
      not work on windows):
    
    
            curl -P le0 ftp.download.com
    
      Download with PORT but use 192.168.0.10 as our IP address to use:
    
            curl -P 192.168.0.10 ftp.download.com
    
    
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    NETWORK INTERFACE
    
      Get a web page from a server using a specified port for the interface:
    
    	curl --interface eth0:1 http://www.netscape.com/
    
      or
    
    	curl --interface 192.168.1.10 http://www.netscape.com/
    
    
    HTTPS
    
      Secure HTTP requires SSL libraries to be installed and used when curl is
      built. If that is done, curl is capable of retrieving and posting documents
      using the HTTPS procotol.
    
      Example:
    
            curl https://www.secure-site.com
    
      Curl is also capable of using your personal certificates to get/post files
      from sites that require valid certificates. The only drawback is that the
      certificate needs to be in PEM-format. PEM is a standard and open format to
      store certificates with, but it is not used by the most commonly used
      browsers (Netscape and MSEI both use the so called PKCS#12 format). If you
      want curl to use the certificates you use with your (favourite) browser, you
      may need to download/compile a converter that can convert your browser's
      formatted certificates to PEM formatted ones. This kind of converter is
      included in recent versions of OpenSSL, and for older versions Dr Stephen
      N. Henson has written a patch for SSLeay that adds this functionality. You
      can get his patch (that requires an SSLeay installation) from his site at:
      http://www.drh-consultancy.demon.co.uk/
    
      Example on how to automatically retrieve a document using a certificate with
      a personal password:
    
            curl -E /path/to/cert.pem:password https://secure.site.com/
    
      If you neglect to specify the password on the command line, you will be
      prompted for the correct password before any data can be received.
    
      Many older SSL-servers have problems with SSLv3 or TLS, that newer versions
      of OpenSSL etc is using, therefore it is sometimes useful to specify what
      SSL-version curl should use. Use -3 or -2 to specify that exact SSL version
      to use:
    
            curl -2 https://secure.site.com/
    
      Otherwise, curl will first attempt to use v3 and then v2.
    
    
      To use OpenSSL to convert your favourite browser's certificate into a PEM
      formatted one that curl can use, do something like this (assuming netscape,
      but IE is likely to work similarly):
    
        You start with hitting the 'security' menu button in netscape. 
    
        Select 'certificates->yours' and then pick a certificate in the list 
    
        Press the 'export' button 
    
        enter your PIN code for the certs 
    
        select a proper place to save it 
    
        Run the 'openssl' application to convert the certificate. If you cd to the
        openssl installation, you can do it like:
    
    
         # ./apps/openssl pkcs12 -in [file you saved] -clcerts -out [PEMfile]
    
    RESUMING FILE TRANSFERS
    
     To continue a file transfer where it was previously aborted, curl supports
     resume on http(s) downloads as well as ftp uploads and downloads.
    
     Continue downloading a document:
    
            curl -c -o file ftp://ftp.server.com/path/file
    
     Continue uploading a document(*1):
    
            curl -c -T file ftp://ftp.server.com/path/file
    
     Continue downloading a document from a web server(*2):
    
            curl -c -o file http://www.server.com/
    
     (*1) = This requires that the ftp server supports the non-standard command
            SIZE. If it doesn't, curl will say so.
    
    
     (*2) = This requires that the web server supports at least HTTP/1.1. If it
    
            doesn't, curl will say so.
    
    TIME CONDITIONS
    
     HTTP allows a client to specify a time condition for the document it
     requests. It is If-Modified-Since or If-Unmodified-Since. Curl allow you to
     specify them with the -z/--time-cond flag.
    
     For example, you can easily make a download that only gets performed if the
     remote file is newer than a local copy. It would be made like:
    
            curl -z local.html http://remote.server.com/remote.html
    
     Or you can download a file only if the local file is newer than the remote
     one. Do this by prepending the date string with a '-', as in:
    
            curl -z -local.html http://remote.server.com/remote.html
    
     You can specify a "free text" date as condition. Tell curl to only download
     the file if it was updated since yesterday:
    
            curl -z yesterday http://remote.server.com/remote.html
    
     Curl will then accept a wide range of date formats. You always make the date
     check the other way around by prepending it with a dash '-'.
    
    DICT
    
      For fun try
    
            curl dict://dict.org/m:curl
            curl dict://dict.org/d:heisenbug:jargon
            curl dict://dict.org/d:daniel:web1913
    
      Aliases for 'm' are 'match' and 'find', and aliases for 'd' are 'define'
      and 'lookup'. For example,
    
            curl dict://dict.org/find:curl
    
      Commands that break the URL description of the RFC (but not the DICT
      protocol) are
    
            curl dict://dict.org/show:db
            curl dict://dict.org/show:strat
    
      Authentication is still missing (but this is not required by the RFC)
    
    LDAP
    
      If you have installed the OpenLDAP library, curl can take advantage of it
      and offer ldap:// support.
    
      LDAP is a complex thing and writing an LDAP query is not an easy task. I do
      advice you to dig up the syntax description for that elsewhere, RFC 1959 if
      no other place is better.
    
      To show you an example, this is now I can get all people from my local LDAP
      server that has a certain sub-domain in their email address:
    
            curl -B "ldap://ldap.frontec.se/o=frontec??sub?mail=*sth.frontec.se"
    
      If I want the same info in HTML format, I can get it by not using the -B
      (enforce ASCII) flag.
    
    ENVIRONMENT VARIABLES
    
      Curl reads and understands the following environment variables:
    
            HTTP_PROXY, HTTPS_PROXY, FTP_PROXY, GOPHER_PROXY
    
      They should be set for protocol-specific proxies. General proxy should be
      set with
            
            ALL_PROXY
    
      A comma-separated list of host names that shouldn't go through any proxy is
      set in (only an asterisk, '*' matches all hosts)
    
            NO_PROXY
    
      If a tail substring of the domain-path for a host matches one of these
      strings, transactions with that node will not be proxied.
    
    
      The usage of the -x/--proxy flag overrides the environment variables.
    
    NETRC
    
      Unix introduced the .netrc concept a long time ago. It is a way for a user
      to specify name and password for commonly visited ftp sites in a file so
      that you don't have to type them in each time you visit those sites. You
      realize this is a big security risk if someone else gets hold of your
      passwords, so therefor most unix programs won't read this file unless it is
      only readable by yourself (curl doesn't care though).
    
      Curl supports .netrc files if told so (using the -n/--netrc option). This is
      not restricted to only ftp, but curl can use it for all protocols where
      authentication is used.
    
      A very simple .netrc file could look something like:
    
    
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            machine curl.haxx.se login iamdaniel password mysecret
    
    
    CUSTOM OUTPUT
    
      To better allow script programmers to get to know about the progress of
      curl, the -w/--write-out option was introduced. Using this, you can specify
      what information from the previous transfer you want to extract.
    
      To display the amount of bytes downloaded together with some text and an
      ending newline:
    
            curl -w 'We downloaded %{size_download} bytes\n' www.download.com
    
    
    KERBEROS4 FTP TRANSFER
    
      Curl supports kerberos4 for FTP transfers. You need the kerberos package
      installed and used at curl build time for it to be used.
    
      First, get the krb-ticket the normal way, like with the kauth tool. Then use
      curl in way similar to:
    
            curl --krb4 private ftp://krb4site.com -u username:fakepwd
    
      There's no use for a password on the -u switch, but a blank one will make
      curl ask for one and you already entered the real password to kauth.
    
    
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    TELNET
    
      The curl telnet support is basic and very easy to use. Curl passes all data
      passed to it on stdin to the remote server. Connect to a remote telnet
      server using a command line similar to:
    
            curl telnet://remote.server.com
    
      And enter the data to pass to the server on stdin. The result will be sent
    
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      to stdout or to the file you specify with -o.
    
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      You might want the -N/--no-buffer option to switch off the buffered output
    
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      for slow connections or similar.
    
      Pass options to the telnet protocol negotiation, by using the -t option. To
      tell the server we use a vt100 terminal, try something like:
    
            curl -tTTYPE=vt100 telnet://remote.server.com
    
      Other interesting options for it -t include:
    
       - XDISPLOC=<X display> Sets the X display location.
    
       - NEW_ENV=<var,val> Sets an environment variable.
    
    
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      NOTE: the telnet protocol does not specify any way to login with a specified
    
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      user and password so curl can't do that automatically. To do that, you need
      to track when the login prompt is received and send the username and
    
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      password accordingly.
    
    
    PERSISTANT CONNECTIONS
    
      Specifying multiple files on a single command line will make curl transfer
      all of them, one after the other in the specified order.
    
      libcurl will attempt to use persistant connections for the transfers so that
      the second transfer to the same host can use the same connection that was
      already initiated and was left open in the previous transfer. This greatly
      decreases connection time for all but the first transfer and it makes a far
      better use of the network.
    
      Note that curl cannot use persistant connections for transfers that are used
      in subsequence curl invokes. Try to stuff as many URLs as possible on the
      same command line if they are using the same host, as that'll make the
    
      transfers faster. If you use a http proxy for file transfers, practicly
      all transfers will be persistant.
    
    
      Persistant connections were introduced in curl 7.7.
    
    
      For your convenience, we have several open mailing lists to discuss curl,
      its development and things relevant to this.
    
      To subscribe to the main curl list, mail curl-request@contactor.se with
      "subscribe <fill in your email address>" in the body.
    
      To subscribe to the curl-library users/deverlopers list, follow the
      instructions at http://curl.haxx.se/mail/
    
      To subscribe to the curl-announce list, to only get information about new
    
      releases, follow the instructions at http://curl.haxx.se/mail/
    
      To subscribe to the curl-and-PHP list in which curl using with PHP is
      discussed, follow the instructions at http://curl.haxx.se/mail/
    
      Please direct curl questions, feature requests and trouble reports to one of
      these mailing lists instead of mailing any individual.