Strcpy on SysV vs. BSD.

[Vadim G. Antonov]

In article <24351 at adm.BRL.MIL> hsw at sparta.com (Howard Weiss) writes:

> Here is a short C program that demonstrates the problem:
>
>main(){
>  char *TTx = "/dev/";
>  char tty[10]; /* works on both SysV and BSD */
>/*  char *tty;	/* works only on BSD */
>  strcpy(tty,TTx);
>  printf("what's in tty now is %s\n",tty);
>}
>
>Yet, the 'char *tty' compiles and runs fine on BSD!

	Generally speaking, it SHOULD NOT work because the only
	thing this program do (commented version) is writing
	bytes "/dev/" into some undefined place pointed by
	uninitialized pointer `tty'. You're lucky: Sys V catched
	you and did not allow you to make a hard mistake.
	Errors of such sort are very easy to put and very hard
	to get (out of the program).

>I've worked on UNIX systems since V6 (in 1976) and I've never seen
>this before.

	I've also worked on Unix V6; but I've ran across
	uninitialized pointers many times! :-)

>Howard Weiss

	Vadim Antonov,
	DEMOS, Moscow, USSR
	(it is NOT a joke)