One more Imagen host software bug

[William LeFebvre]

Sorry for giving this such a wide audience, but I didn't know how else to
reach all the people who recently received a list of bug fixes for the
Imagen host software.

I found one more infinite loop bug, also associated with the tcp
communications software.  I have the feeling that this is the problem I've
been having all along.  There are really two unrelated bugs:  one that
causes a bus error, and a bug in the signal recovery code.

We are running release 2.3, dated July 1986, so these may have been fixed
since then.

The function "udpstatus" returns a pointer to a string that contains the
status line returned by the printer.  The function "updatestatus" in
icomm_tcp.c uses this value as an argument to "sprintf(&note_buf[0],...".
udpstatus reads up to 256 characters from the net, but note_buf is only
128.  Overflowing this buffer would overwrite some critical pointers.  ies
would eventually get a bus error, which would be caught.  Unfortunately,
the signal recovery code ("PHadie" and "PHdie") would somehow get stuck in
an infinite loop.  The following two fixes should cure both aspects of
this particular problem:

File "icomm.h", line 135 reads:

	EXTRN	char	note_buf[128];

and should be

	EXTRN	char	note_buf[512];

(just to be safe---memory is cheap).

File "icomm.c", function "PHdie", line 417 reads:

	exit(rc);

and should read

	_exit(rc);

since "exit" tries to close all open streams (some of which may be
trashed).

	William LeFebvre