Re: snprintf

[Andreas Schwab]

James Morrison <address@hidden> writes:

|>  Hello,
|>         I've noticed that on GNU/Hurd snprintf doesn't work if
|> the expanded template exceeds the size given.
|> 
|> eg
|>         char limited[5];
|>         snprintf(limited,5,"12345");
|> 
|> On GNU/Linux with libio snprintf sets limited to "1234" and returns
|> 5.

This is correct:

        7.19.6.5 The snprintf function

        [#2] The snprintf function is equivalent to fprintf, except that the
        output is written into an array (specified by argument s) rather
        than to a stream. If n is zero, nothing is written, and s may be a
        null pointer. Otherwise, output characters beyond the n-1st are
        discarded rather than being written to the array, and a null
        character is written at the end of the characters actually written
        into the array. If copying takes place between objects that
        overlap, the behavior is undefined.

        Returns

        [#3] The snprintf function returns the number of characters that
        would have been written had n been sufficiently large, not
        counting the terminating null character, or a neg ative value if
        an encoding error occurred. Thus, the null-terminated output has
        been completely written if and only if the returned value is
        nonnegative and less than n.

Andreas.

-- 
Andreas Schwab                                  "And now for something
address@hidden                          completely different."
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