Arrow for a line

[Stepan Kafka]

You may use truetype symbol of arrow for a line e.g. this way (unfortunately, the arrows are along the whole line not only at  line begining ):

SYMBOL
  NAME "arrow"
  TYPE truetype
  FONT arial
  CHARACTER ">"
  GAP -25
END

then
LAYER
...
  CLASS
     STYLE
        SYMBOL arrow
        SIZE 20
        POSITION CC # you may play with (LC, RL, etc - similar to label position) it to achieve different effect - try it
     STYLE
  END # class
END #layer