Tcl

Write Bytes to a Remote SFTP File (BinData)

Demonstrates the Chilkat SFtp.WriteFileBd method, which appends all bytes in a BinData to the remote file identified by an open handle. The first argument is the handle and the second is the BinData.

Note: This example uses a relative local path, which is resolved against the application's current working directory. Absolute local paths may also be used. Supply the path appropriate to your own environment.

Background: This is the binary counterpart to WriteFileText — the right choice for images, archives, or any non-text content, where a charset conversion would corrupt the data. Combined with an appropriate OpenFile disposition it can create, overwrite, or append; here the file is created/truncated first so the result is exactly the BinData contents.

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Tcl


load ./chilkat.dll

set success 0

#  Demonstrates the SFtp.WriteFileBd method, which appends all bytes in a BinData to the remote
#  file identified by an open handle.  The 1st argument is the handle and the 2nd is the BinData.

set sftp [new_CkSFtp]

#  Connect, authenticate, and initialize the SFTP subsystem.
set port 22
set success [CkSFtp_Connect $sftp "sftp.example.com" $port]
if {$success == 0} then {
    puts [CkSFtp_lastErrorText $sftp]
    delete_CkSFtp $sftp
    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.
set password "mySshPassword"

set success [CkSFtp_AuthenticatePw $sftp "mySshLogin" $password]
if {$success == 0} then {
    puts [CkSFtp_lastErrorText $sftp]
    delete_CkSFtp $sftp
    exit
}

set success [CkSFtp_InitializeSftp $sftp]
if {$success == 0} then {
    puts [CkSFtp_lastErrorText $sftp]
    delete_CkSFtp $sftp
    exit
}

#  Open (creating/truncating) the remote file for writing.
set handle [CkSFtp_openFile $sftp "subdir/image.png" "writeOnly" "createTruncate"]
if {[CkSFtp_get_LastMethodSuccess $sftp] == 0} then {
    puts [CkSFtp_lastErrorText $sftp]
    delete_CkSFtp $sftp
    exit
}

#  Put the bytes to write into a BinData.  (Here they are loaded from a local file, but the
#  bytes could come from anywhere.)
set bd [new_CkBinData]

set success [CkBinData_LoadFile $bd "qa_data/image.png"]
if {$success == 0} then {
    puts [CkBinData_lastErrorText $bd]
    delete_CkSFtp $sftp
    delete_CkBinData $bd
    exit
}

#  Append the BinData bytes to the open remote file.
set success [CkSFtp_WriteFileBd $sftp $handle $bd]
if {$success == 0} then {
    puts [CkSFtp_lastErrorText $sftp]
    delete_CkSFtp $sftp
    delete_CkBinData $bd
    exit
}

set success [CkSFtp_CloseHandle $sftp $handle]
if {$success == 0} then {
    puts [CkSFtp_lastErrorText $sftp]
    delete_CkSFtp $sftp
    delete_CkBinData $bd
    exit
}

puts "Wrote [CkBinData_get_NumBytes $bd] bytes."

CkSFtp_Disconnect $sftp

delete_CkSFtp $sftp
delete_CkBinData $bd