Perl

Write Text at a 64-bit Offset in a Remote SFTP File

Demonstrates the Chilkat SFtp.WriteFileText64 method, which encodes text and writes it at a specific 64-bit byte offset in an open handle. The arguments are the handle, the offset, the charset, and the text. The 64-bit offset supports very large files.

Background: A 32-bit offset tops out at about 4 GB, so files larger than that require the 64-bit form to address positions beyond that boundary. The behavior is otherwise identical to the 32-bit version — the only difference is the width of the offset argument, chosen to match the size of the file you are working with.

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Perl

use chilkat();

$success = 0;

#  Demonstrates the SFtp.WriteFileText64 method, which encodes text and writes it at a specific
#  64-bit byte offset in an open handle.  The 1st argument is the handle, the 2nd is the offset,
#  the 3rd is the charset, and the 4th is the text.  The 64-bit offset supports very large files.

$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 = $sftp->openFile("subdir/hugefile.dat","readWrite","openOrCreate");
if ($sftp->get_LastMethodSuccess() == 0) {
    print $sftp->lastErrorText() . "\r\n";
    exit;
}

#  Write at a byte offset beyond the 32-bit (4 GB) range.
$offset = 5000000000;
$success = $sftp->WriteFileText64($handle,$offset,"utf-8","MARKER");
if ($success == 0) {
    print $sftp->lastErrorText() . "\r\n";
    exit;
}

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

print "Wrote at the 64-bit offset." . "\r\n";

$sftp->Disconnect();