A dtksh category 4 command returns a value that can be used in a conditional expression just as in C. If the C function also returns values through reference variables (as in category 2), the dtksh command also uses variable names for the corresponding parameters. Example:
if XmIsTraversable $PUSH_BUTTON; then echo "The pushbutton is traversable" else echo "The pushbutton is not traversable" fi
Generally, the order and type of parameters passed to a command matches those passed to the corresponding C function, except as noted for category 3 commands.