feedback() limitations?

[Seth Teller]

does anyone know if the size of the gl feedback buffer, as passed by
the caller of feedback(), is limited (and if so, why and to what value
it is limited)?  i'm seeing the errors

ERROR #103  feedback: ERR_FEEDBUFTOOBIG
ERROR #17  endfeedback: ERR_NOTINPICK

with a 128k buffer (size = 64k shorts).  i suppose the second 
line is really ERR_NOTINFEEDBACK, but the name assumes people 
doing feedback are doing picking (i'm not).  [i did try R'ing TFM,
but didn't find anything useful.]

second question: are the ERR_* tokens and their meanings described
anywhere?

thanks,

seth