Ruby

Detect End-of-File on a Remote SFTP File

Demonstrates the Chilkat SFtp.Eof method, which returns whether the most recent read for a handle received the SFTP end-of-file status. The only argument is the handle. This example reads until Eof is true.

Background: The timing here is worth understanding: reading exactly through the final byte does not immediately set EOF. The next read succeeds, returns zero bytes, sets the status to SSH_FX_EOF, and only then does Eof report true. That is why the loop tests Eof after each read rather than assuming a short read means the end — a short read can also just be the server returning less than requested.

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Ruby

require 'chilkat'

success = false

#  Demonstrates the SFtp.Eof method, which returns whether the most recent read for a handle
#  received the SFTP end-of-file status.  The only argument is the handle.

sftp = Chilkat::CkSFtp.new()

#  Connect, authenticate, and initialize the SFTP subsystem.
port = 22
success = sftp.Connect("sftp.example.com",port)
if (success == false)
    print sftp.lastErrorText() + "\n";
    exit
end

#  Normally you would not hard-code the password in source.  You should instead obtain it
#  from an interactive prompt, environment variable, or a secrets vault.
password = "mySshPassword"

success = sftp.AuthenticatePw("mySshLogin",password)
if (success == false)
    print sftp.lastErrorText() + "\n";
    exit
end

success = sftp.InitializeSftp()
if (success == false)
    print sftp.lastErrorText() + "\n";
    exit
end

handle = sftp.openFile("subdir/data.txt","readOnly","openExisting")
if (sftp.get_LastMethodSuccess() == false)
    print sftp.lastErrorText() + "\n";
    exit
end

#  Read until Eof reports the end of the file.  Note that reading exactly through the final byte
#  does not set EOF; the next read returns zero bytes and then Eof becomes true.
sbContent = Chilkat::CkStringBuilder.new()
chunkSize = 4096
reading = true
while reading
    chunk = sftp.readFileText(handle,chunkSize,"utf-8")
    if (sftp.LastReadFailed(handle))
        print sftp.lastErrorText() + "\n";
        exit
    end

    sbContent.Append(chunk)
    reading = !sftp.Eof(handle)
end

success = sftp.CloseHandle(handle)
if (success == false)
    print sftp.lastErrorText() + "\n";
    exit
end

print sbContent.getAsString() + "\n";

sftp.Disconnect()