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Re: Strange Behaviour in finding Size of a File

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James Kuyper <jameskuyper@verizon.net> writes:
> On 11/09/2012 03:33 PM, Keith Thompson wrote:
>> Alain Ketterlin <alain@dpt-info.u-strasbg.fr> writes:
>>> Keith Thompson <kst-u@mib.org> writes:
>>>> Alain Ketterlin <alain@dpt-info.u-strasbg.fr> writes:
>>>>> felix <ckpradip@gmail.com> writes:
>>>>>> if ( stat ( logFile, &results ) == 0 )
>>>>>
>>>>> Use ftell() instead (or lseek() at level 2).
>>>>
>>>> What makes you think that will yield better results,
>>>
>>> What makes you think it will not. At least ftell() is C.
>> 
>> We know that stat() isn't working as the OP expects.  I'd expect
>> ftell() to yield exactly the same results -- and it requires opening
>> the file and seeking to the end of it. ...
>
> Opening the file and seeking to the end is not a problem; it's already
> open, or at least it was at the time of the last write, and the current
> write position was presumably at the end of the file, otherwise it
> wouldn't be growing. I'd expect ftell() to give a better indication of
> the bytes written than stat()=>st_size, since I wouldn't expect the
> value returned by ftell() to be affected by issues such as buffering.

Ok, good point.

That's assuming that the program that's querying the size of the file
is the same one that's writing to the file, and that the querying
code has access to the relevant FILE*.  That's not entirely obvious
from the original post, but it seems likely.

(As I said earlier, C doesn't guarantee that the value returned by
ftell() is meaningful for text streams, but that's unlikely to be
an issue for the OP.)

-- 
Keith Thompson (The_Other_Keith) kst-u@mib.org  <http://www.ghoti.net/~kst>
    Will write code for food.
"We must do something.  This is something.  Therefore, we must do this."
    -- Antony Jay and Jonathan Lynn, "Yes Minister"

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Strange Behaviour in finding Size of a File felix <ckpradip@gmail.com> - 2012-11-08 23:09 -0800
  Re: Strange Behaviour in finding Size of a File "Where's all the China Blue food?" <chine.bleu@yahoo.com> - 2012-11-08 23:26 -0800
  Re: Strange Behaviour in finding Size of a File James Kuyper <jameskuyper@verizon.net> - 2012-11-09 06:56 -0500
    Re: Strange Behaviour in finding Size of a File felix <ckpradip@gmail.com> - 2012-11-12 22:23 -0800
      Re: Strange Behaviour in finding Size of a File James Kuyper <jameskuyper@verizon.net> - 2012-11-13 07:27 -0500
        Re: Strange Behaviour in finding Size of a File felix <ckpradip@gmail.com> - 2012-11-19 01:52 -0800
          Re: Strange Behaviour in finding Size of a File James Kuyper <jameskuyper@verizon.net> - 2012-11-19 08:09 -0500
  Re: Strange Behaviour in finding Size of a File Eric Sosman <esosman@comcast-dot-net.invalid> - 2012-11-09 08:24 -0500
    Re: Strange Behaviour in finding Size of a File Nick Keighley <nick_keighley_nospam@hotmail.com> - 2012-11-10 06:06 -0800
      Re: Strange Behaviour in finding Size of a File Ben Bacarisse <ben.usenet@bsb.me.uk> - 2012-11-10 15:12 +0000
        Re: Strange Behaviour in finding Size of a File Ian Collins <ian-news@hotmail.com> - 2012-11-11 08:40 +1300
          Re: Strange Behaviour in finding Size of a File Ben Bacarisse <ben.usenet@bsb.me.uk> - 2012-11-10 20:36 +0000
      Re: Strange Behaviour in finding Size of a File Eric Sosman <esosman@comcast-dot-net.invalid> - 2012-11-10 10:13 -0500
  Re: Strange Behaviour in finding Size of a File John Gordon <gordon@panix.com> - 2012-11-09 15:16 +0000
    Re: Strange Behaviour in finding Size of a File Mark Bluemel <mark_bluemel@pobox.com> - 2012-11-09 15:56 +0000
    Re: Strange Behaviour in finding Size of a File James Kuyper <jameskuyper@verizon.net> - 2012-11-09 11:01 -0500
  Re: Strange Behaviour in finding Size of a File Greg Martin <greg@softsprocket.com> - 2012-11-09 08:59 -0800
  Re: Strange Behaviour in finding Size of a File Alain Ketterlin <alain@dpt-info.u-strasbg.fr> - 2012-11-09 19:42 +0100
    Re: Strange Behaviour in finding Size of a File Keith Thompson <kst-u@mib.org> - 2012-11-09 11:29 -0800
      Re: Strange Behaviour in finding Size of a File Alain Ketterlin <alain@dpt-info.u-strasbg.fr> - 2012-11-09 20:47 +0100
        Re: Strange Behaviour in finding Size of a File Keith Thompson <kst-u@mib.org> - 2012-11-09 12:33 -0800
          Re: Strange Behaviour in finding Size of a File Alain Ketterlin <alain@dpt-info.u-strasbg.fr> - 2012-11-10 02:08 +0100
            Re: Strange Behaviour in finding Size of a File Philip Lantz <prl@canterey.us> - 2012-11-09 18:33 -0800
              Re: Strange Behaviour in finding Size of a File gazelle@shell.xmission.com (Kenny McCormack) - 2012-11-10 02:58 +0000
                Re: Strange Behaviour in finding Size of a File Philip Lantz <prl@canterey.us> - 2012-11-09 23:29 -0800
                Re: Strange Behaviour in finding Size of a File Nick Keighley <nick_keighley_nospam@hotmail.com> - 2012-11-10 06:09 -0800
            Re: Strange Behaviour in finding Size of a File Ian Collins <ian-news@hotmail.com> - 2012-11-10 17:46 +1300
              Re: Strange Behaviour in finding Size of a File James Kuyper <jameskuyper@verizon.net> - 2012-11-10 22:20 -0500
              Re: Strange Behaviour in finding Size of a File Phil Carmody <thefatphil_demunged@yahoo.co.uk> - 2012-11-12 14:01 +0200
            Re: Strange Behaviour in finding Size of a File gazelle@shell.xmission.com (Kenny McCormack) - 2012-11-10 22:01 +0000
          Re: Strange Behaviour in finding Size of a File James Kuyper <jameskuyper@verizon.net> - 2012-11-09 22:14 -0500
            Re: Strange Behaviour in finding Size of a File Keith Thompson <kst-u@mib.org> - 2012-11-09 19:24 -0800
              Re: Strange Behaviour in finding Size of a File James Kuyper <jameskuyper@verizon.net> - 2012-11-09 23:30 -0500
              Re: Strange Behaviour in finding Size of a File Eric Sosman <esosman@comcast-dot-net.invalid> - 2012-11-10 08:32 -0500
                Re: Strange Behaviour in finding Size of a File Ike Naar <ike@sverige.freeshell.org> - 2012-11-10 17:42 +0000
                Re: Strange Behaviour in finding Size of a File Eric Sosman <esosman@comcast-dot-net.invalid> - 2012-11-10 15:19 -0500
  Re: Strange Behaviour in finding Size of a File Keith Thompson <kst-u@mib.org> - 2012-11-09 11:34 -0800

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