recovery.conf restore_command

Hi all,

I was experimenting with the restore_command on one of my standby systems. Originally this command just had:

restore_command='cp /mnt/wallogs/archive/%f %p'

And it was, and is working just fine, but since that doesn't delete the WAL files from the archive directory, I wanted
totry: 

restore_command='pg_standby /mnt/wallogs/archive %f %p %r'

But, the database then refused to start. The log showed:

LOG: entering standby mode
FATAL: could not restore file "00000003.history" from archive: return code 32512
LOG: startup process (PID 22847) existed with exit code 1

Now, that history file was already in the standby's pg_xlog directory. So, I tried copying it back to the archive
directoryand trying again, but no joy. I double-checked the  
permissions on the file and the directory and those were good. So, I just changed the restore_command back to its
originalform, and the standby then started successfully. Did I  
use pg_standby incorrectly? FYI, these servers are streaming replication using Version 9.3.3.
--
Jay