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    Problems connecting to SSL servers.
    ===================================
    
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      It took a very long time before I could sort out why curl had problems
      to connect to certain SSL servers when using SSLeay or OpenSSL v0.9+.
      The error sometimes showed up similar to:
    
      16570:error:1407D071:SSL routines:SSL2_READ:bad mac decode:s2_pkt.c:233:
    
      It turned out to be because many older SSL servers don't deal with SSLv3
      requests properly. To correct this problem, tell curl to select SSLv2 from
      the command line (-2/--sslv2).
    
      I have also seen examples where the remote server didn't like the SSLv2
      request and instead you had to force curl to use SSLv3 with -3/--sslv3.
    
    
    Does curl support resume?
    =========================
    
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      Yes. Both ways on FTP, download ways on HTTP.
    
    
    Is libcurl thread safe?
    =======================
    
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      Yes, as far as curl's own code goes. It does use system calls that often
      aren't thread safe in most environments, such as gethostbyname().
    
      I am very interested in once and for all getting some kind of report or
      README file from those who have used libcurl in a threaded environment,
      since I haven't and I get this question more and more frequently!
    
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    Why doesn't my posting using -F work?
    =====================================
    
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      You can't simply use -F or -d at your choice. The web server that will
      receive your post assumes one of the formats. If the form you're trying to
      "fake" sets the type to 'multipart/form-data', than and only then you must
      use the -F type. In all the most common cases, you should use -d which then
      causes a posting with the type 'application/x-www-form-urlencoded'.
    
    
    Does curl support custom FTP commands?
    ======================================
    
      Yes it does, you can tell curl to perform optional commands both before
      and/or after a file transfer. Study the -Q/--quote option.
    
      Since curl is used for file transfers, you don't use curl to just perform
      ftp commands without transfering anything. Therefore you must always specify
      a URL to transfer to/from even when doing custom FTP commands.
    
    
    Does curl work with other SSL libraries?
    ========================================
    
      Curl has been written to use OpenSSL, although I doubt there would be much
      problems using a different library. I just don't know any other free one and
      that has limited my possibilities to develop against anything else.
    
      If anyone does "port" curl to use a commercial SSL library, I am of course
      very interested in getting the patch!