MESSAGE FORMAT

message format (skeleton) is as follows:

2 bytes		- message length
1 byte		- message type: either of
		  CHAN_GET, CHAN_PUT, CHAN_LIST,
		  CHAN_CLOSE, CHAN_GRANTED, CHAN_NOTGRANTED
		  CHAN_DATA
variable bytes	- message contents


MESSAGE CONTENTS

CHAN_GET: (request)
variable bytes	- file name

CHAN_PUT: (request)
variable bytes	- file name

CHAN_LIST: (request)
(no auxiliary data)

CHAN_CLOSE: (request - information from server that it's closing some channel)
1 byte		- channel number

CHAN_GRANTED: (reply to CHAN_GET/CHAN_PUT/CHAN_LIST)
1 byte		- channel number

CHAN_NOTGRANTED: (reply to CHAN_GET/CHAN_PUT/CHAN_LIST)
(no auxiliary data)


All replies to CHAN_GET/CHAN_PUT/CHAN_LIST are tranferred in CHAN_DATA
messages, they look like this:
1 byte		- channel number
1 byte		- response code (one of CH_CODE_OK / CH_CODE_ERROR)
variable bytes  - reply data

sample data message:
[L][L][T][N][C][.....]

LL - message length
T - message type (CHAN_DATA)
N - channel number
C - code
...., - data

DATA IN REPLY TO LIST REQUEST
[fn1....][fn2....][fn3....]

fn - filenames in ASCIIZ format