I have a legacy script which I am not able to understand.
The script is to transfer 4 files (2 ebcdic format files and 2 pdf files) in unix to mainframes through ftp.>
Put is just the normal scp
scp /path/to/source user@host:/path/to/target
Append only works with a little hack (and not with scp directly)
cat source | ssh user@host "cat >> /path/to/target"