From: utzoo!decvax!ucbvax!info-vax
Newsgroups: fa.info-vax
Title: Re:  Information on Unix/Vax peculiarities
Article-I.D.: ucbvax.217
Posted: Sat Dec  4 16:27:35 1982
Received: Sun Dec  5 09:17:27 1982

>From mark.umcp-cs@UDel-Relay  Sat Dec  4 16:07:34 1982
Mail-From: ARPANET host UDEL-RELAY rcvd at 28-Nov-82 0809-PST
To: Charles F Von Rospach <CHUQUI@Mit-Mc>, unix-wizards@Sri-Csl
Cc: Info-vax@Sri-Csl
Via:  UMCP-CS; 27 Nov 82 20:36-EST
Remailed-Date:  4 Dec 1982 1047-PST
Remailed-From: the tty of Geoffrey S. Goodfellow  <Geoff5 at SRI-CSL>
Remailed-To: Info-VAX@SRI-CSL: ;

I have a program
	which seems to have been written for the PDP11. In bringing it
	up on the Vax, I have been getting funny results. It seems that
	whoever wrote the program is doing some funny things in a large
	integer array, reading and writing into it with a character
	pointer. Since I assume the program did work (its problems are
	much too obvious to have let through), I am assuming that there
	is some problem with how the thing handles internal storage. It
	seems as though it is assuming that an integer is 16bits,
	stored in two bytes in a low/high byte setup. IF I remember my
	PDP11, that is how it stores things. I am rather new to that
	Vax, but I believe it stores things high/low. I am right now
	wondering if there are any other time bombs out there that I
	(and the rest of the net) need to be aware of.
The Vax and the Pdp-11 both use the same byte addresses/packing
scheme in words (which, by the way, actually makes a lot of
sense).  The problem with your program is very likely just that
'int' to Vax C means 32 bits, but to pdp-11 C means '16' bits.
Try declaring the integer array to be 'short int'.