THX, but still cannot find a solution for this problem.
I've created my public and private keys using:
# ssh-keygen -t rsa

[download]
and the public key id_rsa.pub from the client machine was installed on the sftp server.
The user name is absolutely correct.
I can login from the command line to this server and transfer a file without problems:
# sftp  myuser@X.X.X.X
Connecting to X.X.X.X...
sftp> put TEST.txt
Uploading TEST.txt to /HOME/TEST.txt
TEST.txt                             100%   22     0.0KB/s   00:00
sftp> ls
TEST.txt
sftp> rm TEST.txt
Removing /HOME/TEST.txt
sftp> quit

[download]
I cannot understand why this perl script above doesn't work.

In reply to Re^2: transfer a file via SFTP by cc
in thread transfer a file via SFTP by cc

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