Perl

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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Perl

use chilkat();

$success = 0;

#  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 == 0) {
    print $sftp->lastErrorText() . "\r\n";
    exit;
}

#  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 == 0) {
    print $sftp->lastErrorText() . "\r\n";
    exit;
}

$success = $sftp->InitializeSftp();
if ($success == 0) {
    print $sftp->lastErrorText() . "\r\n";
    exit;
}

$handle = $sftp->openFile("subdir/data.txt","readOnly","openExisting");
if ($sftp->get_LastMethodSuccess() == 0) {
    print $sftp->lastErrorText() . "\r\n";
    exit;
}

#  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;
$reading = 1;
while ($reading) {
    $chunk = $sftp->readFileText($handle,$chunkSize,"utf-8");
    if ($sftp->LastReadFailed($handle)) {
        print $sftp->lastErrorText() . "\r\n";
        exit;
    }

    $sbContent->Append($chunk);
    $reading = !$sftp->Eof($handle);
}

$success = $sftp->CloseHandle($handle);
if ($success == 0) {
    print $sftp->lastErrorText() . "\r\n";
    exit;
}

print $sbContent->getAsString() . "\r\n";

$sftp->Disconnect();