Specify the shell in the execution string:
/bin/sh -c 'command' /bin/ksh -c 'command' /bin/csh -c 'command'
This execution string illustrates an action that uses shell piping.
EXEC_STRING /bin/sh -c 'ps | lp'
This is a more complex execution string that requires shell processing and accepts a file argument.
EXEC_STRING /bin/sh -c 'tbl %Arg_1"Man Page:"% | troff -man'
This execution string requires that the argument be a compressed file. The action uncompresses the file and prints it using lp -oraw.
EXEC_STRING /bin/sh -c 'cat %Arg_1 "File to print:"% | \ uncompress | lp -oraw'