Command field customized to execute specific code

Can a command field provide a program to run?

Lets say I want a field to run the kill command

can I have a command field with the function kill.exe (arg1) and it passes the argument I type to kill.exe.

And I don't want a {dlgchooseS}, I just need a STATIC field on my toolbar that passes what I type as an argument to the any function I want.

The closest you can get is to create a user-command that does what you want, giving it a short name, then run it from the FAYT field.

For example, with the user command in the screenshot below you can type ">ff www.example.com" into the file display* and it'll launch that URL in Firefox.

(*So long as it's not displaying a system folder like My Computer or Desktop.)

thanks