1) Allows blocking and non-blocking operations. Namely, it can work in both synchronous and asynchronous modes. 
   I use HttpRequest and NetworkProxy class' asynchronous design here too, since that design proved very effective.

2) Has OPTİONAL network proxy (HTTP_CONNECT, SOCKS4/4a/5) support, using NetworkProxy class.

3) Takes advantage of U++ streams in file upload and download operations, and uses gates for progress tracking when needed.

4) Supports both MD5 and SHA 1 methods.

5) Has SFtp::DirEntry class for easy parsing of directory entries.

#include <Core/Core.h>
#include <SFTP/SFTP.h>

using namespace Upp;

static const char* CRLF = "\r\n";

// This callback allows getting directory entries one by one.
// It is optional.
bool ListDirectory(SFtp::DirEntry& e) 
{

	
	String ls = e.GetEntry();
	if(!ls.IsEmpty())
		// When available, traditiona UNIX style directory listing can be used.
		Cout() << e.GetEntry() << CRLF;
	else {
		Cout() 	<< e.GetName()			        << CRLF
				<< e.GetUserID()		<< CRLF
				<< e.GetGroupID()    	        << CRLF
				<< e.GetSize() 			<< CRLF
				<< e.GetLastAccessed()	        << CRLF
				<< e.GetLastModified()	        << CRLF
				<< "Permissions:"		<< CRLF
				<< "R: " << e.IsReadable() 	<< ", "
				<< "W: " << e.IsWritable() 	<< ", "
				<< "X: " << e.IsExecutable()    << CRLF;
	}
	return false;
}

CONSOLE_APP_MAIN
{
	// This example demonstrates directory listing (ls) and file download operations,
	// using a public SFTP test server.
	// Note that this example uses blocking mode. It is synchronous. 
	// There is also a non-blocking, asynchhronous mode.
	
	FileOut wallpaper("/home/genericuser/Wallpapers/SFTP-download-test-wallpaper.jpg");
	SFtp::DirList dirlist; // SFtp::DirList is a vector containing SFtp:DirEnty elements.

	// Enable logging.
	SFtp::Trace();

	SFtp sftp;
	if(sftp.User("demo-user", "demo-user").Connect("demo.wftpserver.com", 2222)) {
		// Get server banner.
		Cout() << sftp.GetBanner() << CRLF;
		if(sftp.OpenDir("/download") && sftp.ListDir(dirlist, callback(ListDirectory))) {
			if(sftp.Open("/download/F11_wallpaper_06_1600x1200.jpg", SFtp::READ)) {
				if(sftp.Get(wallpaper)) {
				         Cout() << "File successfully downloaded.\r\n";	
                                 	 return;
                                }
		
			}
                }
	}
	Cout() << "Failed.\r\n" << "Reason: " << sftp.GetErrorDesc() << CRLF;
	
	// Instead we could have used the SFtpGet() convenience function.
	// int rc = SFtpGet(wallpaper, "demo-user", "demo-user", "demo-wftpserver.com", 2222, "/download/F11_wallpaper_06_1600x1200.jpg");  
	
}