Function exec( cmd, arg1, arg2, arg3 )

Description:
Executes an operating system command with three arguments.
Parameters:
cmd (String)
name of command
arg1 (String)
the first argument
arg2 (String)
the second argument
arg3 (String)
the third argument
Return Value (String):
short log message
Signature:
java.lang.String exec(java.lang.String, java.lang.String, java.lang.String, java.lang.String)