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POC++, Writing vector<char> to ofstream skips whitespace
 

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  1. POC++, Writing vector<char> to ofstream skips whitespace
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    <p>Despite my sincerest efforts, I cannot seem to locate the bug here. I am writing a vector to an ofstream. The vector contains binary data. However, for some reason, when a whitespace character (0x10, 0x11, 0x12, 0x13, 0x20) is supposed to be written, it is skipped.</p> <p>I have tried using iterators, and a direct ofstream::write().</p> <p>Here is the code I'm using. I've commented out some of the other methods I've tried.</p> <pre><code>void write_file(const std::string&amp; file, std::vector&lt;uint8_t&gt;&amp; v) { std::ofstream out(file, std::ios::binary | std::ios::ate); if (!out.is_open()) throw file_error(file, "unable to open"); out.unsetf(std::ios::skipws); /* ostreambuf_iterator ... std::ostreambuf_iterator&lt;char&gt; out_i(out); std::copy(v.begin(), v.end(), out_i); */ /* ostream_iterator ... std::copy(v.begin(), v.end(), std::ostream_iterator&lt;char&gt;(out, "")); */ out.write((const char*) &amp;v[0], v.size()); } </code></pre> <p>EDIT: And the code to read it back.</p> <pre><code>void read_file(const std::string&amp; file, std::vector&lt;uint8_t&gt;&amp; v) { std::ifstream in(file); v.clear(); if (!in.is_open()) throw file_error(file, "unable to open"); in.unsetf(std::ios::skipws); std::copy(std::istream_iterator&lt;char&gt;(in), std::istream_iterator&lt;char&gt;(), std::back_inserter(v)); } </code></pre> <p>Here is an example input:</p> <pre><code>30 0 0 0 a 30 0 0 0 7a 70 30 0 0 0 32 73 30 0 0 0 2 71 30 0 0 4 d2 </code></pre> <p>And this is the output I am getting when I read it back:</p> <pre><code>30 0 0 0 30 0 0 0 7a 70 30 0 0 0 32 73 30 0 0 0 2 71 30 0 0 4 d2 </code></pre> <p>As you can see, 0x0a is being ommited, ostensibly because it's whitespace.</p> <p>Any suggestions would be greatly appreciated.</p>
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      1. POC++, Writing vector<char> to ofstream skips whitespace
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    1. COShow the code where you read it back.
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      1. POC++, Writing vector<char> to ofstream skips whitespace
      1. USBenjamin Lindley
    2. COWhat does your read code look like? The problem may be there...
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      1. USfbrereto
    3. CODid you check that the contents of the vector are in fact what you expect before write? (E.g. the input step could be removing the whitespace...)
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      1. POC++, Writing vector<char> to ofstream skips whitespace
      1. USBilly ONeal
 

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