libCurl

1. What is libcurl

is free and easy-to-use client-side URL transfer library, supporting DICT, FILE, FTP, FTPS, Gopher, HTTP, HTTPS, LDA, LDAPS, POP3, POP3S, RTMP, RTSP, SCP, SFTP, SMTP, SMTPS, Telnet and TFTP. It supoprts SSL certificates, HTTP POST, HTTP PUT, FTP uploading, HTTO form based upload, proxies, cookies, user+password authebntication (Basic, Digest, NTLM, Negotiate, Kerberos). 

is highly portablem it builds and works identically on numerous performs,including Solaris, NetBSD, FreeBSD, OpenBSD, Darwin, HPUX, IRIX, AIX, Tru64, Linux, UnixWare, HURD, Windows, Amiga, OS/2, BeOs.

is free, thread_safe, IPv6 compatible, feature rich, well supported, fast, thoroughly documented and is already used by many known, big and successfull companies and numerous applications.

2. Using C interface

1) easy interface  - a synchronous, efficient, quickly and easy interface for file transfers.

2) multi interface - a asynchronous brother in the family.

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