Tcl

Pre-Allocate Server Space Before an FTP Upload (ALLO)

Demonstrates the AllocateSize property, which sends the FTP ALLO command to pre-allocate disk space on the server before an upload. Set it to the size in bytes of the file about to be uploaded.

Background: ALLO asks the server to reserve storage in advance, a requirement of certain legacy systems — older mainframes in particular — that need the exact file size up front to allocate a dataset. Modern servers allocate space dynamically and typically ignore or accept ALLO without needing it, so most applications never set this. Provide it only when targeting a host known to require pre-allocation.

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Tcl


load ./chilkat.dll

set success 0

set ftp [new_CkFtp2]

CkFtp2_put_Hostname $ftp "ftp.example.com"
CkFtp2_put_Username $ftp "myFtpLogin"

#  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.
CkFtp2_put_Password $ftp "myPassword"

set success [CkFtp2_Connect $ftp]
if {$success == 0} then {
    puts [CkFtp2_lastErrorText $ftp]
    delete_CkFtp2 $ftp
    exit
}

#  AllocateSize sends the FTP ALLO command to pre-allocate disk space on the server before an
#  upload.  It is rarely needed -- mainly for certain legacy systems that require the exact size
#  in advance -- since most servers allocate space dynamically.  Set it to the size in bytes of
#  the file about to be uploaded.
ERROR: Assignment type mismatch.  ExpressionType=int, atgType=uint

set success [CkFtp2_PutFile $ftp "qa_data/bigfile.zip" "uploads/bigfile.zip"]
if {$success == 0} then {
    puts [CkFtp2_lastErrorText $ftp]
    delete_CkFtp2 $ftp
    exit
}

puts "Uploaded with pre-allocation."

set success [CkFtp2_Disconnect $ftp]
if {$success == 0} then {
    puts [CkFtp2_lastErrorText $ftp]
    delete_CkFtp2 $ftp
    exit
}


delete_CkFtp2 $ftp