Underlying WinSCP file synchronization algorithm

Ive read a lot about the File Synchronization featrue in WinSCP and its keep directory up-to-date method. Ive even tried the feature out. What Im curious to know is that if deep down this synchronization process utilize the rsync algorithm or simply the scp algorithm?

Also, if there any way to use winscp from the command line to set up automated batch files that would transfer files from the command line? Could I invoke winscp from the command line and bypass the gui?

By the way, I think WinSCP is great. Youve obviously put a lot of work into the program. I really enjoy it!

KevDog wrote:

Ive read a lot about the File Synchronization featrue in WinSCP and its keep directory up-to-date method. Ive even tried the feature out. What Im curious to know is that if deep down this synchronization process utilize the rsync algorithm or simply the scp algorithm?

WinSCP uses it own algorithm, because with SFTP you cannot use rsync.

Also, if there any way to use winscp from the command line to set up automated batch files that would transfer files from the command line? Could I invoke winscp from the command line and bypass the gui?

Not yet :-(

A few questions about the synchronization process:
1. Is it true that SFTP only encrypts the command channel but not the data channel?
2. Do you have any plans on adding rsync or unison file synchronization capability that would handle the synchronization process?
3. Does SFTP only compare timestamps to determine if a file has changed, and if so, does it copy or syncs the newest version of the file in its entireity? (No underlying diff/patch algorithm)

Thanks

KevDog wrote:

1. Is it true that SFTP only encrypts the command channel but not the data channel?

No. There's no command/data channel as with FTP, there is only one channel and it is whole encrypted. The above may be true for FTPS (FTP over SSL), but I do not know.

2. Do you have any plans on adding rsync or unison file synchronization capability that would handle the synchronization process?

No.

3. Does SFTP only compare timestamps to determine if a file has changed

Yes. There is no other way with SFTP. The latest version 5 of SFTP specification defines MD5 hashing function, but AFAIK there's no server that supports it yet.

and if so, does it copy or syncs the newest version of the file in its entireity? (No underlying diff/patch algorithm)

The above is not supportted by SFTP.