Use this syntax for the file argument:
%Arg_n%
or
%(File)Arg_n%
(File) is optional, since arguments supplied to Arg_n are assumed (by default) to be files. (See "Interpreting a File Argument as a String" for use of the %(String)Arg_n% syntax.)
This syntax lets the user drop a data file object on the action icon to start the action with that file argument. It substitutes the nth argument into the command line. The file can be a local or remote file.
This execution string executes wc -w using a dropped file as the -load parameter.
EXEC_STRING wc -w %Arg_1%
This example shows a portion of a definition for an action that works only with directory arguments. When a directory is dropped on the action icon, the action displays a list of all the files in the directory with read-write permission.
ACTION List_Writable_Files { ARG_TYPE FOLDER EXEC_STRING /bin/sh -c 's -l %Arg_1% | grep rw-' ... }