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Binary files often are read/written using structs. The struct representation in memory must exactly match to that of the binary data (you have to care about alignments; any new member variable should be allocated at a byte offset that is a multiple of 4 or 8 (depending on compiler settings); or you disable alignment by #pragma). Then, you could read data by record rather than by bytes. You also could handle different records or read whole (rest of) file to a byte array.<br />
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Regards, Alex<br />

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Binary files often are read/written using structs. The struct representation in memory must exactly match to that of the binary data (you have to care about alignments; any new member variable should be allocated at a byte offset that is a multiple of 4 or 8 (depending on compiler settings); or you disable alignment by #pragma). Then, you could read data by record rather than by bytes. You also could handle different records or read whole (rest of) file to a byte array.

Regards, Alex


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im trying to read width and height property of a BMP image file like:<br />
<br />
&nbsp; &nbsp; ifstream bmp(file_name.c_str(), ios::binary);<br />
&nbsp; &nbsp; if(!bmp) throw string(&quot;unable to open &quot;&nbsp;+ file_name + &quot;!&quot;);<br />
&nbsp; &nbsp; unsigned int width( 0), height(0); &nbsp;<br />
&nbsp; &nbsp; bmp.seekg(18); &nbsp; //move to &nbsp;width/height position <br />
&nbsp; &nbsp; bmp &gt;&gt;&nbsp;width;<br />
&nbsp; &nbsp; bmp &gt;&gt;&nbsp;height;<br />
&nbsp; &nbsp; <br />
just nothing happens, though reading chars is okay. isnt ifstream::operator&gt;&gt; supposed to deal with ints also(like istream does)? dont want to use the ugly ifstream::read(...)<br />
&nbsp;<br />
<br />
<br />

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im trying to read width and height property of a BMP image file like:

    ifstream bmp(file_name.c_str(), ios::binary);
    if(!bmp) throw string("unable to open " + file_name + "!");
    unsigned int width( 0), height(0);  
    bmp.seekg(18);   //move to  width/height position 
    bmp >> width;
    bmp >> height;
    
just nothing happens, though reading chars is okay. isnt ifstream::operator>> supposed to deal with ints also(like istream does)? dont want to use the ugly ifstream::read(...)
 




ifstream::operator&gt;&gt; problem

C++ is an intermediate-level general-purpose programming language, not to be confused with C or C#. It was developed as a set of extensions to the C programming language to improve type-safety and add support for automatic resource management, object-orientation, generic programming, and exception handling, among other features.

ifstream::operator&gt;&gt; problem

ifstream::operator>> problem