The minimum requirements for a COMMAND
action are two fields—ACTION
and EXEC_STRING.
ACTION action_name
{
EXEC_STRING execution_string
} |
The execution string is the most important part of a COMMAND
action definition. It uses syntax similar to the command line you
would execute in a Terminal window but includes additional syntax
for handling file and string arguments.
General Features of Execution
Strings |
 |
Execution strings may include:
File and non-file
arguments
Absolute paths or names of executables
An argument is information required by a command or application
for it to run properly. For example, consider the command line you
could use to open a file in Text Editor:
In this command filename
is a file argument of the dtpad
command.
Actions, like applications and commands, can have arguments.
There are two types of data that a COMMAND
action can use:
Using Shells in Execution
Strings
The execution string is executed directly, rather than through
a shell. However, you can explicitly invoke a shell in the execution
string.
For example:
EXEC_STRING \
/bin/sh -c \
'tar -tvf %(File)Arg_1% 2>&1 | \${PAGER:-more};\
echo "\\n*** Select Close from the Window menu to close ***"' |
Name or Absolute Path of the
Executable
If your application is located in a directory listed in the
PATH variable, you can use the simple executable name. If the application
is elsewhere, you must use the
absolute path to the executable file.
Creating
an Action that Uses No Arguments |
|
Use the same syntax for the EXEC_STRING
that you would use to start the application from a command line.
This execution string
is part of an action that starts the X client xcutsel.
This execution string starts the client xclock
with a digital clock. The command line includes a command-line option
but requires no arguments.
EXEC_STRING xclock -digital |
Creating
an Action that Accepts a Dropped File |
|
Use this syntax for the file argument:
or
(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 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 'ls -l %Arg_1% | grep rw-'
...
} |
Creating
an Action that Prompts for a File Argument |
|
Use this syntax for the file argument:
This syntax creates an action that displays a prompt for a
file name when the user double-clicks the action icon.
For example, this execution string displays a dialog box that
prompts for the file argument of the wc -w
command:
EXEC_STRING wc -w %(File)"Count words in file:"% |
Creating
an Action that Accepts a Dropped File or Prompts for One |
|
Use this syntax for the file argument:
or
This syntax produces an action that:
Accepts a dropped
file as the file argument.
Displays a dialog box that prompts for a file name
when the user double- clicks the action icon.
For example, this execution string performs lp
-oraw on a dropped file.
If the action is started by double-clicking the icon, a dialog box
appears prompting for the file name.
EXEC_STRING lp -oraw %Arg_1"File to print:"% |
Creating
an Action that Prompts for a Non-File Argument |
|
Use this syntax for the non-file parameter:
or
(String) is optional,
since quoted text is interpreted, by default, as string data. This
syntax displays a dialog box that prompts for non-file data; do
not use this syntax when prompting for a file name.
For example, this execution string runs the xwd
command and prompts for a value to be added to each pixel:
EXEC_STRING xwd -add %"Add value:"% -out %Arg_1"Filename:"% |
Interpreting
a File Argument as a String |
|
Use this syntax for the argument:
For example, this execution string prints a file with a banner
containing the file name, using the command lp -tbanner filename.
EXEC_STRING lp -t%(String)Arg_1% %(File)Arg_1"File to print:"% |
Providing
Shell Capabilities in an Action |
|
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' |
This execution string
starts a shell script.
EXEC_STRING /usr/local/bin/StartGnuClient |
Creating COMMAND Actions for
Multiple File Arguments |
|
There are three ways for actions to handle multiple file arguments:
The action can be
run repreatedly, once for each argument. When an EXEC_STRING
contains a single file argument and multiple file arguments are
provided by dropping multiple files on the action icon, the action
is run separately for each file argument.
For example if multiple file arguments are supplied to the
following action definition:
ACTION DisplayScreenImage
{
EXEC_STRING xwud -in %Arg_1%
...
} |
the DisplayScreenImage action is run repeatedly.
The action can use two or more non-interchangeable
file arguments. For example:
xsetroot -cursor cursorfile maskfile |
requires two unique files in a particular order.
The action can perform the same command sequentially
on each file argument. For example:
will print one or many files in one print job.
Creating
an Action for Non-Interchangeable Arguments
Use one of the following syntax conventions:
If you want the
action to prompt for the file names, use this syntax for each file
argument:
Use a different prompt
string for each argument.
For example, this execution string prompts for two files.
EXEC_STRING xsetroot -cursor %(File)"Cursor bitmap:"% \
%(File)"Mask bitmap:"% |
To accept dropped files, use this syntax for each
file argument:
using different values of n
for each argument. For example:
EXEC_STRING diff %Arg_1% %Arg_2% |
Creating
an Action with Interchangeable File Arguments
Use one of the following syntax conventions:
To create an action
that accepts dropped files and issues a command in the form command file1
file2
..., use this syntax for the file arguments:
To create an action that accepts multiple dropped
files, or displays a prompt for a single file when double-clicked,
use this syntax for the file arguments:
The action will issue the command in the form: command file1
file2
....
This execution string
creates an action that executes:
with multiple file arguments.
This execution string creates an action similar
to the previous example, except that the action displays a prompt
when double-clicked (no file arguments).
EXEC_STRING pr %Arg_1"File(s) to print:"% %Args% |
Creating
an Action for Multiple Dropped Files
To accept multiple dropped file arguments and execute a command
line in the form:
use the syntax:
This execution string
executes a script named Checkout for multiple files:
EXEC_STRING /usr/local/bin/Checkout \
%Arg_1"Check out what file?"% %Args% |
This execution string
executes lp -oraw with multiple
files:
EXEC_STRING lp -oraw %Arg_1"File to print:"% %Args% |
Printable version
