[no subject]

[REM at MIT-MC (Robert Elton Maas)]

Is there any way in MacLISP to open a file in read-modify-write mode?
(I.e. you can read data in from random places, and you can overwrite
existing data with new data or extend the end of the file with new data.)
I hoped APPEND mode of NEWIO would work, but it forbids reading.
I need to be able to read in words containing 8-bit bytes and write
back out data with some bytes changed and others left as read-in.