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Re: how to do this?

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James Kuyper wrote:
> On 11/14/2015 07:10 PM, Ian Collins wrote:
>> bilsch01 wrote:
> ....
>>>     Oh.  The vec1 , vec2 . . . aren't null terminated.  I don't see any
>>> way to fix that.
>>
>> Your code as written implied that they were null terminated by using
>> strxxx functions to compare and copy them.
>
> True. However, he opened the file in text mode, which means that even if
> null characters were written to that file, there's no guarantee that
> they'll still be there when read back from the file. That's because of
> 7.21.2p2:
>
> "Data read in from a text stream will necessarily compare equal to the
> data that were earlier written out to that stream only if: the data
> consist only of printing characters and the control characters
> horizontal tab and new-line; no new-line character is immediately
> preceded by space characters; and the last character is a new-line
> character."
>
> Therefore, if a file contains null characters, it should be read in
> binary mode, not text mode.

Good spot!

-- 
Ian Collins

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Thread

how to do this? bilsch01 <king621@comcast.net> - 2015-11-14 12:09 -0800
  Re: how to do this? Rosario19 <Ros@invalid.invalid> - 2015-11-14 21:49 +0100
  Re: how to do this? Ian Collins <ian-news@hotmail.com> - 2015-11-15 10:02 +1300
    Re: how to do this? Ian Collins <ian-news@hotmail.com> - 2015-11-15 10:17 +1300
    Re: how to do this? bilsch01 <king621@comcast.net> - 2015-11-14 15:16 -0800
      Re: how to do this? James Kuyper <jameskuyper@verizon.net> - 2015-11-14 18:24 -0500
        Re: how to do this? bilsch01 <king621@comcast.net> - 2015-11-14 15:30 -0800
          Re: how to do this? Lew Pitcher <lew.pitcher@digitalfreehold.ca> - 2015-11-14 19:01 -0500
          Re: how to do this? James Kuyper <jameskuyper@verizon.net> - 2015-11-14 19:07 -0500
  Re: how to do this? Ian Collins <ian-news@hotmail.com> - 2015-11-15 11:26 +1300
    Re: how to do this? bilsch01 <king621@comcast.net> - 2015-11-14 15:07 -0800
      Re: how to do this? James Kuyper <jameskuyper@verizon.net> - 2015-11-14 18:17 -0500
      Re: how to do this? bilsch01 <king621@comcast.net> - 2015-11-14 15:25 -0800
        Re: how to do this? Ian Collins <ian-news@hotmail.com> - 2015-11-15 13:10 +1300
          Re: how to do this? James Kuyper <jameskuyper@verizon.net> - 2015-11-14 19:21 -0500
            Re: how to do this? Ian Collins <ian-news@hotmail.com> - 2015-11-15 13:24 +1300
        Re: how to do this? James Kuyper <jameskuyper@verizon.net> - 2015-11-14 19:12 -0500
          Re: how to do this? Ian Collins <ian-news@hotmail.com> - 2015-11-15 13:18 +1300
            Re: how to do this? James Kuyper <jameskuyper@verizon.net> - 2015-11-14 19:23 -0500
  Re: how to do this? bilsch01 <king621@comcast.net> - 2015-11-14 15:18 -0800

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