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    .TH curl 1 "25 Jan 2005" "Curl 7.13.0" "Curl Manual"
    
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    curl \- transfer a URL
    
    .SH SYNOPSIS
    .B curl [options]
    
    .I [URL...]
    
    .SH DESCRIPTION
    .B curl
    
    is a tool to transfer data from or to a server, using one of the supported
    protocols (HTTP, HTTPS, FTP, FTPS, GOPHER, DICT, TELNET, LDAP or FILE). The
    command is designed to work without user interaction.
    
    
    curl offers a busload of useful tricks like proxy support, user
    authentication, ftp upload, HTTP post, SSL (https:) connections, cookies, file
    
    transfer resume and more. As you will see below, the amount of features will
    make your head spin!
    
    curl is powered by libcurl for all transfer-related features. See
    .BR libcurl (3)
    for details.
    
    .SH URL
    The URL syntax is protocol dependent. You'll find a detailed description in
    RFC 2396.
    
    You can specify multiple URLs or parts of URLs by writing part sets within
    braces as in:
    
     http://site.{one,two,three}.com
    
    or you can get sequences of alphanumeric series by using [] as in:
    
     ftp://ftp.numericals.com/file[1-100].txt
     ftp://ftp.numericals.com/file[001-100].txt    (with leading zeros)
     ftp://ftp.letters.com/file[a-z].txt
    
    
    No nesting of the sequences is supported at the moment, but you can use
    several ones next to each other:
    
     http://any.org/archive[1996-1999]/vol[1-4]/part{a,b,c}.html
    
    You can specify any amount of URLs on the command line. They will be fetched
    in a sequential manner in the specified order.
    
    Curl will attempt to re-use connections for multiple file transfers, so that
    getting many files from the same server will not do multiple connects /
    handshakes. This improves speed. Of course this is only done on files
    specified on a single command line and cannot be used between separate curl
    invokes.
    
    .SH OPTIONS
    .IP "-a/--append"
    
    (FTP) When used in an FTP upload, this will tell curl to append to the target
    file instead of overwriting it. If the file doesn't exist, it will be created.
    
    
    If this option is used twice, the second one will disable append mode again.
    
    .IP "-A/--user-agent <agent string>"
    
    (HTTP) Specify the User-Agent string to send to the HTTP server. Some badly
    done CGIs fail if its not set to "Mozilla/4.0".  To encode blanks in the
    string, surround the string with single quote marks.  This can also be set
    with the \fI-H/--header\fP option of course.
    
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    If this option is set more than once, the last one will be the one that's
    
    .IP "--anyauth"
    (HTTP) Tells curl to figure out authentication method by itself, and use the
    most secure one the remote site claims it supports. This is done by first
    doing a request and checking the response-headers, thus inducing an extra
    network round-trip. This is used instead of setting a specific authentication
    
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    method, which you can do with \fI--basic\fP, \fI--digest\fP, \fI--ntlm\fP, and
    
    \fI--negotiate\fP. (Added in 7.10.6)
    
    
    Note that using --anyauth is not recommended if you do uploads from stdin,
    since it may require data to be sent twice and then the client must be able to
    rewind. If the need should arise when uploading from stdin, the upload
    operation will fail.
    
    
    If this option is used several times, the following occurrences make no
    difference.
    
    .IP "-b/--cookie <name=data>"
    (HTTP)
    Pass the data to the HTTP server as a cookie. It is supposedly the
    data previously received from the server in a "Set-Cookie:" line.
    The data should be in the format "NAME1=VALUE1; NAME2=VALUE2".
    
    If no '=' letter is used in the line, it is treated as a filename to use to
    read previously stored cookie lines from, which should be used in this session
    
    if they match. Using this method also activates the "cookie parser" which will
    make curl record incoming cookies too, which may be handy if you're using this
    
    in combination with the \fI-L/--location\fP option. The file format of the
    file to read cookies from should be plain HTTP headers or the Netscape/Mozilla
    cookie file format.
    
    \fBNOTE\fP that the file specified with \fI-b/--cookie\fP is only used as
    input. No cookies will be stored in the file. To store cookies, use the
    \fI-c/--cookie-jar\fP option or you could even save the HTTP headers to a file
    using \fI-D/--dump-header\fP!
    
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    If this option is set more than once, the last one will be the one that's
    
    .IP "-B/--use-ascii"
    
    Enable ASCII transfer when using FTP or LDAP. For FTP, this can also be
    enforced by using an URL that ends with ";type=A". This option causes data
    sent to stdout to be in text mode for win32 systems.
    
    
    If this option is used twice, the second one will disable ASCII usage.
    
    .IP "--basic"
    (HTTP) Tells curl to use HTTP Basic authentication. This is the default and
    this option is usually pointless, unless you use it to override a previously
    set option that sets a different authentication method (such as \fI--ntlm\fP,
    \fI--digest\fP and \fI--negotiate\fP). (Added in 7.10.6)
    
    If this option is used several times, the following occurrences make no
    difference.
    
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    .IP "--ciphers <list of ciphers>"
    (SSL) Specifies which ciphers to use in the connection. The list of ciphers
    must be using valid ciphers. Read up on SSL cipher list details on this URL:
    
    \fIhttp://www.openssl.org/docs/apps/ciphers.html\fP
    
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    If this option is used several times, the last one will override the others.
    
    .IP "--compressed"
    
    (HTTP) Request a compressed response using one of the algorithms libcurl
    supports, and return the uncompressed document.  If this option is used and
    the server sends an unsupported encoding, Curl will report an error.
    
    If this option is used several times, each occurrence will toggle it on/off.
    
    .IP "--connect-timeout <seconds>"
    Maximum time in seconds that you allow the connection to the server to take.
    This only limits the connection phase, once curl has connected this option is
    
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    of no more use. See also the \fI-m/--max-time\fP option.
    
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    If this option is used several times, the last one will be used.
    
    .IP "-c/--cookie-jar <file name>"
    Specify to which file you want curl to write all cookies after a completed
    operation. Curl writes all cookies previously read from a specified file as
    well as all cookies received from remote server(s). If no cookies are known,
    no file will be written. The file will be written using the Netscape cookie
    
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    file format. If you set the file name to a single dash, "-", the cookies will
    
    be written to stdout.
    
    .B NOTE
    If the cookie jar can't be created or written to, the whole curl operation
    won't fail or even report an error clearly. Using -v will get a warning
    displayed, but that is the only visible feedback you get about this possibly
    lethal situation.
    
    
    If this option is used several times, the last specified file name will be
    
    used.
    
    .IP "-C/--continue-at <offset>"
    
    Continue/Resume a previous file transfer at the given offset. The given offset
    is the exact number of bytes that will be skipped counted from the beginning
    
    of the source file before it is transferred to the destination.  If used with
    
    uploads, the ftp server command SIZE will not be used by curl.
    
    Use "-C -" to tell curl to automatically find out where/how to resume the
    transfer. It then uses the given output/input files to figure that out.
    
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    If this option is used several times, the last one will be used.
    
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    .IP "--create-dirs"
    
    When used in conjunction with the -o option, curl will create the necessary
    local directory hierarchy as needed. This option creates the dirs mentioned
    with the -o option, nothing else. If the -o file name uses no dir or if the
    dirs it mentions already exist, no dir will be created.
    
    To create remote directories when using FTP, try \fI--ftp-create-dirs\fP.
    
    .IP "--crlf"
    (FTP) Convert LF to CRLF in upload. Useful for MVS (OS/390).
    
    If this option is used twice, the second will again disable crlf converting.
    
    .IP "-d/--data <data>"
    
    (HTTP) Sends the specified data in a POST request to the HTTP server, in a way
    that can emulate as if a user has filled in a HTML form and pressed the submit
    button. Note that the data is sent exactly as specified with no extra
    processing (with all newlines cut off).  The data is expected to be
    
    \&"url-encoded". This will cause curl to pass the data to the server using the
    
    content-type application/x-www-form-urlencoded. Compare to \fI-F/--form\fP. If
    this option is used more than once on the same command line, the data pieces
    specified will be merged together with a separating &-letter. Thus, using '-d
    
    name=daniel -d skill=lousy' would generate a post chunk that looks like
    
    
    If you start the data with the letter @, the rest should be a file name to
    
    read the data from, or - if you want curl to read the data from stdin.  The
    contents of the file must already be url-encoded. Multiple files can also be
    
    specified. Posting data from a file named 'foobar' would thus be done with
    
    \fI--data\fP @foobar".
    
    To post data purely binary, you should instead use the \fI--data-binary\fP
    option.
    
    \fI-d/--data\fP is the same as \fI--data-ascii\fP.
    
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    If this option is used several times, the ones following the first will
    
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    .IP "--data-ascii <data>"
    
    (HTTP) This is an alias for the \fI-d/--data\fP option.
    
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    If this option is used several times, the ones following the first will
    
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    .IP "--data-binary <data>"
    
    (HTTP) This posts data in a similar manner as \fI--data-ascii\fP does,
    although when using this option the entire context of the posted data is kept
    as-is. If you want to post a binary file without the strip-newlines feature of
    the \fI--data-ascii\fP option, this is for you.
    
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    If this option is used several times, the ones following the first will
    
    .IP "--digest"
    
    (HTTP) Enables HTTP Digest authentication. This is a authentication that
    prevents the password from being sent over the wire in clear text. Use this in
    
    combination with the normal \fI-u/--user\fP option to set user name and
    
    password. See also \fI--ntlm\fP, \fI--negotiate\fP and \fI--anyauth\fP for
    
    related options. (Added in curl 7.10.6)
    
    If this option is used several times, the following occurrences make no
    difference.
    .IP "--disable-eprt"
    (FTP) Tell curl to disable the use of the EPRT and LPRT commands when doing
    active FTP transfers. Curl will normally always first attempt to use EPRT,
    then LPRT before using PORT, but with this option, it will use PORT right
    away. EPRT and LPRT are extensions to the original FTP protocol, may not work
    on all servers but enable more functionality in a better way than the
    
    traditional PORT command. (Added in 7.10.5)
    
    If this option is used several times, each occurrence will toggle this on/off.
    
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    .IP "--disable-epsv"
    (FTP) Tell curl to disable the use of the EPSV command when doing passive FTP
    
    transfers. Curl will normally always first attempt to use EPSV before PASV,
    
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    but with this option, it will not try using EPSV.
    
    
    If this option is used several times, each occurrence will toggle this on/off.
    
    .IP "-D/--dump-header <file>"
    
    Write the protocol headers to the specified file.
    
    This option is handy to use when you want to store the headers that a HTTP
    site sends to you. Cookies from the headers could then be read in a second
    
    curl invoke by using the \fI-b/--cookie\fP option! The \fI-c/--cookie-jar\fP
    option is however a better way to store cookies.
    
    When used on FTP, the ftp server response lines are considered being "headers"
    and thus are saved there.
    
    
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    If this option is used several times, the last one will be used.
    
    .IP "-e/--referer <URL>"
    
    (HTTP) Sends the "Referer Page" information to the HTTP server. This can also
    
    be set with the \fI-H/--header\fP flag of course.  When used with
    
    \fI-L/--location\fP you can append ";auto" to the referer URL to make curl
    automatically set the previous URL when it follows a Location: header. The
    ";auto" string can be used alone, even if you don't set an initial referer.
    
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    If this option is used several times, the last one will be used.
    
    .IP "--engine <name>"
    Select the OpenSSL crypto engine to use for cipher
    operations. Use \fI--engine list\fP to print a list of build-time supported
    engines. Note that not all (or none) of the engines may be available at
    run-time.
    
    .IP "--environment"
    (RISC OS ONLY) Sets a range of environment variables, using the names the -w
    option supports, to easier allow extraction of useful information after having
    run curl.
    
    If this option is used several times, each occurrence will toggle this on/off.
    
    .IP "--egd-file <file>"
    (HTTPS) Specify the path name to the Entropy Gathering Daemon socket. The
    socket is used to seed the random engine for SSL connections. See also the
    
    \fI--random-file\fP option.
    
    .IP "-E/--cert <certificate[:password]>"
    (HTTPS)
    Tells curl to use the specified certificate file when getting a file
    with HTTPS. The certificate must be in PEM format.
    If the optional password isn't specified, it will be queried for on
    the terminal. Note that this certificate is the private key and the private
    certificate concatenated!
    
    If this option is used several times, the last one will be used.
    .IP "--cert-type <type>"
    (SSL) Tells curl what certificate type the provided certificate is in. PEM,
    DER and ENG are recognized types.
    
    
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    If this option is used several times, the last one will be used.
    
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    .IP "--cacert <CA certificate>"
    (HTTPS) Tells curl to use the specified certificate file to verify the
    
    peer. The file may contain multiple CA certificates. The certificate(s) must
    be in PEM format.
    
    
    curl recognizes the environment variable named 'CURL_CA_BUNDLE' if that is
    set, and uses the given path as a path to a CA cert bundle. This option
    overrides that variable.
    
    The windows version of curl will automatically look for a CA certs file named
    \'curl-ca-bundle.crt\', either in the same directory as curl.exe, or in the
    Current Working Directory, or in any folder along your PATH.
    
    
    If this option is used several times, the last one will be used.
    .IP "--capath <CA certificate directory>"
    (HTTPS) Tells curl to use the specified certificate directory to verify the
    
    peer. The certificates must be in PEM format, and the directory must have been
    
    processed using the c_rehash utility supplied with openssl. Using
    \fI--capath\fP can allow curl to make https connections much more efficiently
    than using \fI--cacert\fP if the \fI--cacert\fP file contains many CA
    certificates.
    
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    If this option is used several times, the last one will be used.
    
    .IP "-f/--fail"
    
    (HTTP) Fail silently (no output at all) on server errors. This is mostly done
    like this to better enable scripts etc to better deal with failed attempts. In
    normal cases when a HTTP server fails to deliver a document, it returns a HTML
    document stating so (which often also describes why and more). This flag will
    prevent curl from outputting that and fail silently instead.
    
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    If this option is used twice, the second will again disable silent failure.
    
    .IP "--ftp-account [data]"
    (FTP) 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)
    
    If this option is used twice, the second will override the previous use.
    
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    .IP "--ftp-create-dirs"
    (FTP) When an FTP URL/operation uses a path that doesn't currently exist on
    
    the server, the standard behavior of curl is to fail. Using this option, curl
    
    will instead attempt to create missing directories. (Added in 7.10.7)
    
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    If this option is used twice, the second will again disable silent failure.
    .IP "--ftp-pasv"
    (FTP) Use PASV when transfering. PASV is the internal default behavior, but
    
    using this option can be used to override a previous --ftp-port option. (Added
    
    in 7.11.0)
    
    If this option is used twice, the second will again disable silent failure.
    .IP "--ftp-ssl"
    (FTP) Make the FTP connection switch to use SSL/TLS. (Added in 7.11.0)
    
    
    If this option is used twice, the second will again disable this.
    
    .IP "-F/--form <name=content>"
    
    (HTTP) This lets curl emulate a filled in form in which a user has pressed the
    
    submit button. This causes curl to POST data using the Content-Type
    
    multipart/form-data according to RFC1867. This enables uploading of binary
    
    files etc. To force the 'content' part to be a file, prefix the file name
    
    with an @ sign. To just get the content part from a file, prefix the file name
    with the letter <. The difference between @ and < is then that @ makes a file
    get attached in the post as a file upload, while the < makes a text field and
    just get the contents for that text field from a file.
    
    Example, to send your password file to the server, where
    
    \&'password' is the name of the form-field to which /etc/passwd will be the
    
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    \fBcurl\fP -F password=@/etc/passwd www.mypasswords.com
    
    To read the file's content from stdin instead of a file, use - where the file
    
    name should've been. This goes for both @ and < constructs.
    
    You can also tell curl what Content-Type to use by using 'type=', in a manner
    similar to:
    
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    \fBcurl\fP -F "web=@index.html;type=text/html" url.com
    
    
    or
    
    \fBcurl\fP -F "name=daniel;type=text/foo" url.com
    
    
    You can also explicitly change the name field of an file upload part by
    setting filename=, like this:
    
    \fBcurl\fP -F "file=@localfile;filename=nameinpost" url.com
    
    
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    See further examples and details in the MANUAL.
    
    
    This option can be used multiple times.
    
    .IP "-g/--globoff"
    This option switches off the "URL globbing parser". When you set this option,
    you can specify URLs that contain the letters {}[] without having them being
    interpreted by curl itself. Note that these letters are not normal legal URL
    
    contents but they should be encoded according to the URI standard.
    
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    .IP "-G/--get"
    
    When used, this option will make all data specified with \fI-d/--data\fP or
    \fI--data-binary\fP to be used in a HTTP GET request instead of the POST
    request that otherwise would be used. The data will be appended to the URL
    with a '?'  separator.
    
    
    If used in combination with -I, the POST data will instead be appended to the
    URL with a HEAD request.
    
    If used multiple times, nothing special happens.
    
    .IP "-h/--help"
    Usage help.
    .IP "-H/--header <header>"
    
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    (HTTP) Extra header to use when getting a web page. You may specify any number
    of extra headers. Note that if you should add a custom header that has the
    same name as one of the internal ones curl would use, your externally set
    header will be used instead of the internal one. This allows you to make even
    
    trickier stuff than curl would normally do. You should not replace internally
    
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    set headers without knowing perfectly well what you're doing. Replacing an
    internal header with one without content on the right side of the colon will
    prevent that header from appearing.
    
    See also the \fI-A/--user-agent\fP and \fI-e/--referer\fP options.
    
    
    This option can be used multiple times to add/replace/remove multiple headers.
    
    .IP "-i/--include"
    (HTTP)
    Include the HTTP-header in the output. The HTTP-header includes things
    like server-name, date of the document, HTTP-version and more...
    
    
    If this option is used twice, the second will again disable header include.
    
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    .IP "--interface <name>"
    Perform an operation using a specified interface. You can enter interface
    name, IP address or host name. An example could look like:
    
    
     curl --interface eth0:1 http://www.netscape.com/
    
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    If this option is used several times, the last one will be used.
    
    .IP "-I/--head"
    
    Fetch the HTTP-header only! HTTP-servers feature the command HEAD
    which this uses to get nothing but the header of a document. When used
    
    on a FTP or FILE file, curl displays the file size and last modification
    time only.
    
    
    If this option is used twice, the second will again disable header only.
    
    .IP "-j/--junk-session-cookies"
    (HTTP) When curl is told to read cookies from a given file, this option will
    
    make it discard all "session cookies". This will basically have the same effect
    
    as if a new session is started. Typical browsers always discard session
    cookies when they're closed down. (Added in 7.9.7)
    
    If this option is used several times, each occurrence will toggle this on/off.
    
    (SSL) This option explicitly allows curl to perform "insecure" SSL connections
    and transfers. Starting with curl 7.10, all SSL connections will be attempted
    to be made secure by using the CA certificate bundle installed by
    default. This makes all connections considered "insecure" to fail unless
    
    \fI-k/--insecure\fP is used.
    
    If this option is used twice, the second time will again disable it.
    
    .IP "--key <key>"
    (SSL) Private key file name. Allows you to provide your private key in this
    separate file.
    
    If this option is used several times, the last one will be used.
    .IP "--key-type <type>"
    (SSL) Private key file type. Specify which type your \fI--key\fP provided
    private key is. DER, PEM and ENG are supported.
    
    If this option is used several times, the last one will be used.
    
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    .IP "--krb4 <level>"
    (FTP) Enable kerberos4 authentication and use. The level must be entered and
    should be one of 'clear', 'safe', 'confidential' or 'private'. Should you use
    a level that is not one of these, 'private' will instead be used.
    
    This option requires that the library was built with kerberos4 support. This
    
    is not very common. Use \fI-V/--version\fP to see if your curl supports it.
    
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    If this option is used several times, the last one will be used.
    
    .IP "-K/--config <config file>"
    
    Specify which config file to read curl arguments from. The config file is a
    text file in which command line arguments can be written which then will be
    used as if they were written on the actual command line. Options and their
    parameters must be specified on the same config file line. If the parameter is
    to contain white spaces, the parameter must be inclosed within quotes.  If the
    first column of a config line is a '#' character, the rest of the line will be
    treated as a comment.
    
    
    Specify the filename as '-' to make curl read the file from stdin.
    
    Note that to be able to specify a URL in the config file, you need to specify
    
    it using the \fI--url\fP option, and not by simply writing the URL on its own
    
    line. So, it could look similar to this:
    
    url = "http://curl.haxx.se/docs/"
    
    
    This option can be used multiple times.
    
    .IP "--limit-rate <speed>"
    Specify the maximum transfer rate you want curl to use. This feature is useful
    
    if you have a limited pipe and you'd like your transfer not use your entire
    bandwidth.
    
    The given speed is measured in bytes/second, unless a suffix is appended.
    Appending 'k' or 'K' will count the number as kilobytes, 'm' or M' makes it
    megabytes while 'g' or 'G' makes it gigabytes. Examples: 200K, 3m and 1G.
    
    
    If you are also using the \fI-Y/--speed-limit\fP option, that option will take
    
    precedence and might cripple the rate-limiting slightly, to help keeping the
    speed-limit logic working.
    
    This option was introduced in curl 7.10.
    
    
    If this option is used several times, the last one will be used.
    
    .IP "-l/--list-only"
    (FTP)
    When listing an FTP directory, this switch forces a name-only view.
    Especially useful if you want to machine-parse the contents of an FTP
    directory since the normal directory view doesn't use a standard look
    or format.
    
    This option causes an FTP NLST command to be sent.  Some FTP servers
    list only files in their response to NLST; they do not include
    subdirectories and symbolic links.
    
    
    If this option is used twice, the second will again disable list only.
    
    .IP "-L/--location"
    
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    (HTTP/HTTPS) If the server reports that the requested page has a different
    location (indicated with the header line Location:) this flag will let curl
    
    attempt to reattempt the get on the new place. If used together with
    \fI-i/--include\fP or \fI-I/--head\fP, headers from all requested pages will
    be shown. If authentication is used, curl will only send its credentials to
    the initial host, so if a redirect takes curl to a different host, it won't
    intercept the user+password. See also \fI--location-trusted\fP on how to
    change this.
    
    
    If this option is used twice, the second will again disable location following.
    .IP "--location-trusted"
    
    (HTTP/HTTPS) Like \fI-L/--location\fP, but will allow sending the name +
    password to all hosts that the site may redirect to. This may or may not
    introduce a security breach if the site redirects you do a site to which
    you'll send your authentication info (which is plaintext in the case of HTTP
    Basic authentication).
    
    
    If this option is used twice, the second will again disable location following.
    
    .IP "--max-filesize <bytes>"
    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 curl will
    return with exit code 63.
    
    NOTE: 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.
    
    .IP "-m/--max-time <seconds>"
    
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    Maximum time in seconds that you allow the whole operation to take.  This is
    useful for preventing your batch jobs from hanging for hours due to slow
    
    networks or links going down.  This doesn't work fully in win32 systems.  See
    also the \fI--connect-timeout\fP option.
    
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    If this option is used several times, the last one will be used.
    
    .IP "-M/--manual"
    Manual. Display the huge help text.
    .IP "-n/--netrc"
    
    Makes curl scan the \fI.netrc\fP file in the user's home directory for login
    name and password. This is typically used for ftp on unix. If used with http,
    curl will enable user authentication. See
    
    .BR netrc(4)
    
    for details on the file format. Curl will not complain if that file
    hasn't the right permissions (it should not be world nor group
    readable). The environment variable "HOME" is used to find the home
    directory.
    
    
    A quick and very simple example of how to setup a \fI.netrc\fP to allow curl
    to ftp to the machine host.domain.com with user name \&'myself' and password
    'secret' should look similar to:
    
    
    .B "machine host.domain.com login myself password secret"
    
    
    If this option is used twice, the second will again disable netrc usage.
    
    .IP "--netrc-optional"
    Very similar to \fI--netrc\fP, but this option makes the .netrc usage
    \fBoptional\fP and not mandatory as the \fI--netrc\fP does.
    
    .IP "--negotiate"
    (HTTP) Enables GSS-Negotiate authentication. The GSS-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 be also used along
    with another authentication methods. For more information see IETF draft
    draft-brezak-spnego-http-04.txt. (Added in 7.10.6)
    
    
    This option requires that the library was built with GSSAPI support. This is
    
    not very common. Use \fI-V/--version\fP to see if your version supports
    
    
    If this option is used several times, the following occurrences make no
    difference.
    
    .IP "-N/--no-buffer"
    Disables the buffering of the output stream. In normal work situations, curl
    will use a standard buffered output stream that will have the effect that it
    will output the data in chunks, not necessarily exactly when the data arrives.
    Using this option will disable that buffering.
    
    
    If this option is used twice, the second will again switch on buffering.
    
    .IP "--ntlm"
    (HTTP) Enables NTLM authentication. The NTLM authentication method was
    designed by Microsoft and is used by IIS web servers. It is a proprietary
    protocol, reversed engineered by clever people and implemented in curl based
    on their efforts. This kind of behavior should not be endorsed, you should
    encourage everyone who uses NTLM to switch to a public and documented
    authentication method instead. Such as Digest. (Added in 7.10.6)
    
    
    If you want to enable NTLM for your proxy authentication, then use
    \fI--proxy-ntlm\fP.
    
    
    This option requires that the library was built with SSL support. Use
    
    \fI-V/--version\fP to see if your curl supports NTLM.
    
    
    If this option is used several times, the following occurrences make no
    difference.
    
    .IP "-o/--output <file>"
    Write output to <file> instead of stdout. If you are using {} or [] to fetch
    multiple documents, you can use '#' followed by a number in the <file>
    specifier. That variable will be replaced with the current string for the URL
    being fetched. Like in:
    
      curl http://{one,two}.site.com -o "file_#1.txt"
    
    or use several variables like:
    
      curl http://{site,host}.host[1-5].com -o "#1_#2"
    
    You may use this option as many times as you have number of URLs.
    
    See also the \fI--create-dirs\fP option to create the local directories
    dynamically.
    
    .IP "-O/--remote-name"
    
    Write output to a local file named like the remote file we get. (Only the file
    part of the remote file is used, the path is cut off.)
    
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    The remote file name to use for saving is extracted from the given URL.
    Nothing else
    
    
    You may use this option as many times as you have number of URLs.
    
    .IP "--pass <phrase>"
    (SSL) Pass phrase for the private key
    
    If this option is used several times, the last one will be used.
    
    .IP "--proxy-basic"
    Tells curl to use HTTP Basic authentication when communicating with the given
    proxy. Use \fI--basic\fP for enabling HTTP Basic with a remote host. Basic is
    the default authentication method curl uses with proxies.
    
    If this option is used twice, the second will again disable proxy HTTP Basic
    authentication.
    
    .IP "--proxy-digest"
    Tells curl to use HTTP Digest authentication when communicating with the given
    proxy. Use \fI--digest\fP for enabling HTTP Digest with a remote host.
    
    If this option is used twice, the second will again disable proxy HTTP Digest.
    
    Tells curl to use HTTP NTLM authentication when communicating with the given
    
    proxy. Use \fI--ntlm\fP for enabling NTLM with a remote host.
    
    If this option is used twice, the second will again disable proxy HTTP NTLM.
    
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    .IP "-p/--proxytunnel"
    
    When an HTTP proxy is used (\fI-x/--proxy\fP), this option will cause non-HTTP
    protocols to attempt to tunnel through the proxy instead of merely using it to
    do HTTP-like operations. The tunnel approach is made with the HTTP proxy
    CONNECT request and requires that the proxy allows direct connect to the
    remote port number curl wants to tunnel through to.
    
    
    If this option is used twice, the second will again disable proxy tunnel.
    
    .IP "-P/--ftp-port <address>"
    (FTP) Reverses the initiator/listener roles when connecting with ftp. This
    switch makes Curl use the PORT command instead of PASV. In practice, PORT
    tells the server to connect to the client's specified address and port, while
    PASV asks the server for an ip address and port to connect to. <address>
    should be one of:
    
    .IP interface
    
    i.e "eth0" to specify which interface's IP address you want to use  (Unix only)
    
    .IP "IP address"
    
    i.e "192.168.10.1" to specify exact IP number
    
    .IP "host name"
    
    i.e "my.host.domain" to specify machine
    
    .IP "-"
    
    (any single-letter string) to make it pick the machine's default
    .RE
    
    If this option is used several times, the last one will be used. Disable the
    
    use of PORT with \fI--ftp-pasv\fP. Disable the attempt to use the EPRT command
    instead of PORT by using \fI--disable-eprt\fP. EPRT is really PORT++.
    
    If used as the first parameter on the command line, the \fI$HOME/.curlrc\fP
    
    file will not be read and used as a config file.
    .IP "-Q/--quote <comand>"
    
    (FTP) Send an arbitrary command to the remote FTP server. Quote commands are
    
    sent BEFORE the transfer is taking place (just after the initial PWD command
    to be exact). To make commands take place after a successful transfer, prefix
    them with a dash '-'. To make commands get sent after libcurl has changed
    working directory, just before the transfer command(s), prefix the command
    with '+'. You may specify any amount of commands. If the server returns
    
    failure for one of the commands, the entire operation will be aborted. You
    must send syntactically correct FTP commands as RFC959 defines.
    
    .IP "--random-file <file>"
    (HTTPS) Specify the path name to file containing what will be considered as
    random data. The data is used to seed the random engine for SSL connections.
    
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    See also the \fI--egd-file\fP option.
    
    .IP "-r/--range <range>"
    (HTTP/FTP)
    Retrieve a byte range (i.e a partial document) from a HTTP/1.1 or FTP
    server. Ranges can be specified in a number of ways.
    .RS
    .TP 10
    .B 0-499
    specifies the first 500 bytes
    .TP
    .B 500-999
    specifies the second 500 bytes
    .TP
    .B -500
    specifies the last 500 bytes
    .TP
    .B 9500
    specifies the bytes from offset 9500 and forward
    .TP
    .B 0-0,-1
    specifies the first and last byte only(*)(H)
    .TP
    .B 500-700,600-799
    specifies 300 bytes from offset 500(H)
    .TP
    .B 100-199,500-599
    specifies two separate 100 bytes ranges(*)(H)
    .RE
    
    (*) = NOTE that this will cause the server to reply with a multipart
    response!
    
    You should also be aware that many HTTP/1.1 servers do not have this feature
    enabled, so that when you attempt to get a range, you'll instead get the whole
    document.
    
    FTP range downloads only support the simple syntax 'start-stop' (optionally
    with one of the numbers omitted). It depends on the non-RFC command SIZE.
    
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    If this option is used several times, the last one will be used.
    
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    .IP "-R/--remote-time"
    When used, this will make libcurl attempt to figure out the timestamp of the
    remote file, and if that is available make the local file get that same
    timestamp.
    
    If this option is used twice, the second time disables this again.
    
    .IP "--retry <num>"
    If a transient error is returned when curl tries to perform a transfer, it
    will retry this number of times before giving up. Setting the number to 0
    
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    makes curl do no retries (which is the default). Transient error means either:
    a timeout, an FTP 5xx response code or an HTTP 5xx response code.
    
    
    When curl is about to retry a transfer, it will first wait one second and then
    for all forthcoming retries it will double the waiting time until it reaches
    
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    10 minutes which then will be the delay between the rest of the retries.  By
    using \fI--retry-delay\fP you disable this exponential backoff algorithm. See
    also \fI--retry-max-time\fP to limit the total time allowed for
    retries. (Option added in 7.12.3)
    
    If this option is used multiple times, the last occurrence decide the amount.
    
    .IP "--retry-delay <seconds>"
    Make curl sleep this amount of time between each retry when a transfer has
    failed with a transient error (it changes the default backoff time algorithm
    
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    between retries). This option is only interesting if \fI--retry\fP is also
    used. Setting this delay to zero will make curl use the default backoff time.
    (Option added in 7.12.3)
    
    If this option is used multiple times, the last occurrence decide the amount.
    
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    .IP "--retry-max-time <seconds>"
    The retry timer is reset before the first transfer attempt. Retries will be
    done as usual (see \fI--retry\fP) as long as the timer hasn't reached this
    given limit. Notice that if the timer hasn't reached the limit, the request
    will be made and while performing, it may take longer than this given time
    period. To limit a single request\'s maximum time, use \fI-m/--max-time\fP.
    Set this option to zero to not timeout retries. (Option added in 7.12.3)
    
    If this option is used multiple times, the last occurrence decide the amount.
    
    .IP "-s/--silent"
    Silent mode. Don't show progress meter or error messages.  Makes
    Curl mute.
    
    
    If this option is used twice, the second will again disable mute.
    
    .IP "-S/--show-error"
    When used with -s it makes curl show error message if it fails.
    
    
    If this option is used twice, the second will again disable show error.
    
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    .IP "--socks <host[:port]>"
    Use the specified SOCKS5 proxy. If the port number is not specified, it is
    assumed at port 1080. (Option added in 7.11.1)
    
    This option overrides any previous use of \fI-x/--proxy\fP, as they are
    mutually exclusive.
    
    If this option is used several times, the last one will be used.
    
    .IP "--stderr <file>"
    Redirect all writes to stderr to the specified file instead. If the file name
    is a plain '-', it is instead written to stdout. This option has no point when
    you're using a shell with decent redirecting capabilities.
    
    If this option is used several times, the last one will be used.
    
    .IP "--tcp-nodelay"
    Turn on the TCP_NODELAY option. See the \fIcurl_easy_setopt(3)\fP man page for
    details about this option. (Added in 7.11.2)
    
    
    If this option is used several times, each occurrence toggles this on/off.
    
    .IP "-t/--telnet-option <OPT=val>"
    Pass options to the telnet protocol. Supported options are:
    
    TTYPE=<term> Sets the terminal type.
    
    XDISPLOC=<X display> Sets the X display location.
    
    NEW_ENV=<var,val> Sets an environment variable.
    
    .IP "-T/--upload-file <file>"
    
    This transfers the specified local file to the remote URL. If there is no file
    part in the specified URL, Curl will append the local file name. NOTE that you
    must use a trailing / on the last directory to really prove to Curl that there
    is no file name or curl will think that your last directory name is the remote
    file name to use. That will most likely cause the upload operation to fail. If
    
    this is used on a http(s) server, the PUT command will be used.
    
    Use the file name "-" (a single dash) to use stdin instead of a given file.
    
    
    Before 7.10.8, when this option was used several times, the last one was used.
    
    In curl 7.10.8 and later, you can specify one -T for each URL on the command
    line. Each -T + URL pair specifies what to upload and to where. curl also
    supports "globbing" of the -T argument, meaning that you can upload multiple
    files to a single URL by using the same URL globbing style supported in the
    URL, like this:
    
    curl -T "{file1,file2}" http://www.uploadtothissite.com
    
    or even
    
    curl -T "img[1-1000].png" ftp://ftp.picturemania.com/upload/
    
    .IP "--trace <file>"
    Enables a full trace dump of all incoming and outgoing data, including
    
    descriptive information, to the given output file. Use "-" as filename to have
    the output sent to stdout.
    
    If this option is used several times, the last one will be used. (Added in
    
    .IP "--trace-ascii <file>"
    Enables a full trace dump of all incoming and outgoing data, including
    descriptive information, to the given output file. Use "-" as filename to have
    the output sent to stdout.
    
    
    This is very similar to \fI--trace\fP, but leaves out the hex part and only
    shows the ASCII part of the dump. It makes smaller output that might be easier
    to read for untrained humans.
    
    If this option is used several times, the last one will be used. (Added in
    
    .IP "-u/--user <user:password>"
    
    Specify user and password to use for server authentication. Overrides
    \fI-n/--netrc\fP and \fI--netrc-optional\fP.
    
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    If this option is used several times, the last one will be used.
    
    .IP "-U/--proxy-user <user:password>"
    
    Specify user and password to use for proxy authentication.
    
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    If this option is used several times, the last one will be used.
    
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    .IP "--url <URL>"
    
    Specify a URL to fetch. This option is mostly handy when you want to specify
    
    URL(s) in a config file.
    
    
    This option may be used any number of times. To control where this URL is
    
    written, use the \fI-o/--output\fP or the \fI-O/--remote-name\fP options.
    
    .IP "-v/--verbose"
    
    Makes the fetching more verbose/talkative. Mostly usable for debugging. Lines
    starting with '>' means data sent by curl, '<' means data received by curl
    that is hidden in normal cases and lines starting with '*' means additional
    info provided by curl.
    
    
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    Note that if you only want HTTP headers in the output, \fI-i/--include\fP
    
    might be option you're looking for.
    
    If you think this option still doesn't give you enough details, consider using
    \fI--trace\fP or \fI--trace-ascii\fP instead.
    
    
    If this option is used twice, the second will again disable verbose.
    
    .IP "-V/--version"
    
    Displays information about curl and the libcurl version it uses.
    
    The first line includes the full version of curl, libcurl and other 3rd party
    libraries linked with the executable.
    
    The second line (starts with "Protocols:") shows all protocols that libcurl
    reports to support.
    
    The third line (starts with "Features:") shows specific features libcurl
    
    reports to offer. Available features include:
    .RS
    .IP "IPv6"
    You can use IPv6 with this.
    .IP "krb4"
    Krb4 for ftp is supported.
    .IP "SSL"
    HTTPS and FTPS are supported.
    .IP "libz"
    Automatic decompression of compressed files over HTTP is supported.
    .IP "NTLM"
    
    NTLM authentication is supported.
    
    Negotiate authentication is supported.
    
    .IP "Debug"
    This curl uses a libcurl built with Debug. This enables more error-tracking
    and memory debugging etc. For curl-developers only!
    .IP "AsynchDNS"
    This curl uses asynchronous name resolves.
    .IP "SPNEGO"
    
    SPNEGO Negotiate authentication is supported.
    
    .IP "Largefile"
    This curl supports transfers of large files, files larger than 2GB.
    
    .IP "IDN"
    This curl supports IDN - international domain names.
    
    .IP "-w/--write-out <format>"
    Defines what to display after a completed and successful operation. The format
    is a string that may contain plain text mixed with any number of variables. The
    string can be specified as "string", to get read from a particular file you
    specify it "@filename" and to tell curl to read the format from stdin you
    write "@-".
    
    The variables present in the output format will be substituted by the value or
    text that curl thinks fit, as described below. All variables are specified
    like %{variable_name} and to output a normal % you just write them like
    
    %%. You can output a newline by using \\n, a carriage return with \\r and a tab
    
    space with \\t.
    
    .B NOTE:
    The %-letter is a special letter in the win32-environment, where all
    occurrences of % must be doubled when using this option.
    
    Available variables are at this point:
    .RS
    .TP 15
    .B url_effective
    The URL that was fetched last. This is mostly meaningful if you've told curl
    to follow location: headers.
    .TP
    .B http_code
    The numerical code that was found in the last retrieved HTTP(S) page.
    .TP
    
    .B http_connect
    The numerical code that was found in the last response (from a proxy) to a
    curl CONNECT request. (Added in 7.12.4)
    .TP
    
    .B time_total
    The total time, in seconds, that the full operation lasted. The time will be
    displayed with millisecond resolution.
    .TP
    .B time_namelookup
    The time, in seconds, it took from the start until the name resolving was
    completed.
    .TP
    .B time_connect
    The time, in seconds, it took from the start until the connect to the remote
    host (or proxy) was completed.
    .TP
    .B time_pretransfer
    The time, in seconds, it took from the start until the file transfer is just
    about to begin. This includes all pre-transfer commands and negotiations that
    are specific to the particular protocol(s) involved.
    .TP
    
    .B time_redirect
    The time, in seconds, it took for all redirection steps include name lookup,
    connect, pretransfer and transfer before final transaction was
    started. time_redirect shows the complete execution time for multiple
    redirections. (Added in 7.12.3)
    .TP
    
    .B time_starttransfer
    The time, in seconds, it took from the start until the first byte is just about
    
    to be transferred. This includes time_pretransfer and also the time the
    
    server needs to calculate the result.
    .TP
    
    .B size_download
    The total amount of bytes that were downloaded.
    .TP
    .B size_upload
    The total amount of bytes that were uploaded.
    .TP
    
    .B size_header
    The total amount of bytes of the downloaded headers.
    .TP
    .B size_request
    The total amount of bytes that were sent in the HTTP request.
    .TP
    
    .B speed_download
    The average download speed that curl measured for the complete download.
    .TP
    .B speed_upload
    
    The average upload speed that curl measured for the complete upload.