Now that you have written the module that determines whether to accept or reject an incoming message, the next step is to write a Global Inbound Script to pre-process the incoming messages. This Global Inbound Script does the following:

• It calls the reject_message function, which you defined in the previous section, to determine whether to accept or reject the incoming message.

• It changes the segment delimiter from 0x0D to 0x0B to ensure that the message can be parsed. (Recall that the VMD file expects the segment delimiter to be 0x0B. This was set when you created the VMD file. See Creating the Customized ACK/NACK VMD File for more details.)

To create the Global Inbound Script:

• In Chameleon, select Global Inbound Script from the Chameleon menu.

• In the Global Inbound Script window that appears, type the following script:

from reject_evn import *

try:
  global reject
  reject = reject_message(value)
except Exception, error:
  print error

# We configured the VMD file to expect 0x0B ('\v') after each segment, so
# we have to replace the real segment delimiters ('\r').
#
value = value.replace('\r', '\v')

This Global Inbound Script uses the variable reject to indicate whether a message should be accepted or rejected. This variable will be accessed by the Segment Outbound Script that you will create in the following section.