Sybase SQL Anywhere 17 - Can a database trigger call a system command?

I have a Sybase SQL Anywhere 17 server running on Linux, and I was wondering if it is possible to create a database trigger to execute a local operating system system command when an UPDATE is down on a particular database record? Essentially, if a database table.field is updated to "complete", execute /usr/local/bin/notify I have done this previously with other database systems, but looking over the SQLAW17 documentation, I can't find any references on how to do this (the trigger documentation seems to refer to stored procedures etc, not clear if I can or should do this as a stored procedure, etc). Any advice would be appreciated!