The Code

Mike Baker wrote this padhack.tcl script, which modifies resource group 32, items 19 and 21, which supply values to the Start Recording and StopRecording options.

#!/tvbin/tivosh

EnableTransactionHoldoff true

set db [dbopen]
RetryTransaction {
  # get handles to the right database entries
  set swsysa [db $db open "/SwSystem/ACTIVE"]
  set tmpgrp [dbobj $swsysa get ResourceGroup 32]

  # add new values for the start recording times
  set tmpres [dbobj $tmpgrp get "Item" 19]
  dbobj $tmpres set String "On-time|0|1 minute early|60|2 minutes↵
  early|120|3 minutes early|180|4 minutes early|240|5 minutes early|300|10↵
  minutes early|600|1 minute late|-60|2 minutes late|-120|3 minutes late|↵
  -180|4 minutes late|-240|5 minutes late|-300|10 minutes late|-600|"↵
  # add new values for the stop recording times↵
  set tmpres [dbobj $tmpgrp get "Item" 21]

  dbobj $tmpres set String "On-time|0|1 minute longer|60|2 minutes↵
  longer|120|5 minutes longer|300|15 minutes longer|900|30 minutes↵
  longer|1800|1 hour longer|3600|1 1/2 hours longer|5400|3 hours↵
  longer|10800|1 minute shorter|-60|2 minutes shorter|-120|3 minute↵
  shorter|-180|4 minutes shorter|-240|5 minutes shorter|-300|10 minutes↵
  shorter| 600|"
  
  dbobj $tmpgrp remove "CompressedFile"
}

To understand how this works, run dump.tcl and find resource group 32. You'll see that item 19 dictates values for the Start Recording offset, and item 21 controls the Stop Recording offsets:

32 19 {On-time|0|1 minute early|60|2 minutes early|120|3 minutes early|180|4 
minutes early|240|5 minutes early|300|10 minutes early|600|}
...
32 21 {On-time|0|1 minute longer|60|2 minutes longer|120|5 
minutes longer|300|15 minutes longer|900|30 minutes longer|1800|1 hour longer|3600|1 
1/2 hours longer|5400|3 hours longer|10800|}

Save the code as padhack.tcl in TiVo's /var/hack/bin directory and make it executable:

bash-2.02# chmod 755 /var/hack/bin/padhack.tcl