Re: atoi return


"Keith Thompson" <kst-u@xxxxxxx> wrote in message
news:ln1vyokqw1.fsf@xxxxxxxxxxxxxxxxxx

[snip]

Here's the point. If you give atoi() a string that doesn't represent
a number, such as the string "bad", it returns 0. If you give it the
string "0", which does represent a number it returns 0. If atoi()
returns 0, you *can't tell* whether it successfully converted the
string "0" or failed to convert the string "bad".

Even worse, if atoi() is given a string that represents a number
that's too big to hold in an int, it invokes undefined behavior. For
example, there's no telling what atoi("99999999999999999999") will do;
it could crash your program or worse.

I see. Must be a left over dinosaur like gets().

Bill


.

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