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Re: std::ifstream multithread

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On 5/27/2011 6:22 AM, Philipp Kraus wrote:
> I must read a lot of files like this
>
> std::ifstream l_file;
>
> l_file.open(p_str1.c_str(), std::ifstream::binary);
> std::copy( std::istream_iterator<char>(l_file),
> std::istream_iterator<char>(),
> std::ostreambuf_iterator<char>(&l_deflate) );
> l_file.close();
>
> I deflate the file content with bzip. I would do this in a multithread
> content, so my question is, can I do this without any problems during
> reading?
> In some cases two thread can use the same file (p_str1 is in two threads
> equal). Can i read the same file out of two thread or is a mutex required?

You need to consult your compiler and/or standard library manual.  C++ 
(as it stands now) claims nothing WRT threads and reentrancy.  In the 
new Standard there are specific provisions for supporting 
multithreading, but not in the current one.

V
-- 
I do not respond to top-posted replies, please don't ask

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std::ifstream multithread Philipp Kraus <philipp.kraus@flashpixx.de> - 2011-05-27 12:22 +0200
  Re: std::ifstream multithread Victor Bazarov <v.bazarov@comcast.invalid> - 2011-05-27 08:31 -0400
    Re: std::ifstream multithread Philipp Kraus <philipp.kraus@flashpixx.de> - 2011-05-27 15:04 +0200
      Re: std::ifstream multithread Victor Bazarov <v.bazarov@comcast.invalid> - 2011-05-27 09:19 -0400
        Re: std::ifstream multithread Philipp Kraus <philipp.kraus@flashpixx.de> - 2011-05-27 16:51 +0200
  Re: std::ifstream multithread Jorgen Grahn <grahn+nntp@snipabacken.se> - 2011-05-27 15:17 +0000

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