🚀 go-pugleaf

lipson@dms.agames.com (Pete Lipson) writes:

>  if you say:   strncpy(dst,"abcdef",4)

> does the standard really say you get five characters appended to the
>dst (the chars 'a' 'b' 'c' 'd' AND the '\0') ???
>  the man-page says it moves AT MOST the count (4 in this case) characters
>but it ALSO says it returns a pointer to a NULL-TERMINATED result.

Only if it hits a null before it copies n chars:

7.11.2.4:

"The strncpy function copies not more than n characters (characters
that follow a null character are not copied) from the array pointed to
by s2 to the array pointed to by s1. [134]"

"[134] Thus, if there is no null character in the first n characters
that can end up in the array pointed to by s2, the result will not be
null-terminated."

I suspect you are getting 4 chars from s2 and the '\0' is already in
s1.

BTW, the standard also says:

"If the array pointed to by s2 is a string that is shorter than n
characters, null characters are appended to the copy in the array
pointed to by s1, until n characters in all have been written"

I wonder how many implementations do this?

dhs   spencer@panix.com