Chilkat2-Python

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.

Chilkat Chilkat2-Python Downloads

Download Chilkat for Chilkat2-Python

Chilkat2-Python

import sys
import chilkat2

success = False

ftp = chilkat2.Ftp2()

ftp.Hostname = "ftp.example.com"
ftp.Username = "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.
ftp.Password = "myPassword"

success = ftp.Connect()
if (success == False):
    print(ftp.LastErrorText)
    sys.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

success = ftp.PutFile("qa_data/bigfile.zip","uploads/bigfile.zip")
if (success == False):
    print(ftp.LastErrorText)
    sys.exit()

print("Uploaded with pre-allocation.")

success = ftp.Disconnect()
if (success == False):
    print(ftp.LastErrorText)
    sys.exit()