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  1. PO
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    <p>Cast pMemory to the correct type and move it around from pMemory to pMemory + size of the mapped memory - size of the type to which you refer...</p> <p>In other words, you have effectively allocated memory and associated the menory with a file that is changed as you change the memory.</p> <p>In <code>C</code> assuming pMemory is the pointer returned by <code>MapViewOfFile</code>:</p> <pre><code>int x = (*(int *)pMemory); // Read the first int char c = (*(char *)pMemory); // Read the first char typedef struct oddball { int x, int y, int z, char str[256] } oddball; // assume the typedef syntax is right... oddball *p = (oddball *)pMemory; // point to the base of the mapped memory p += 14; // p now points to the 15th instance of oddball in the file. // Or... p = &amp;p[14]; p-&gt;x = 0; p-&gt;y = 0; p-&gt;z = 0; strcpy( p-&gt;str( "This is the 0, 0, 0 position" ) ); // You've now changed the memory to which p[14] refers. // To read every byte... (Again in C, use the compiler to generate asm // Assumes: // fileSize is the size of the mapped memory in bytes // pMemory is the pointer returned by MapViewOfFile // buffer is a block of memory that will hold n bytes // pos is the position from which you want to read // n is the number of bytes to read from position pos and the smallest size in bytes to which buffer can point void readBytes( unsigned int fileSize, char *pMemory, char *buffer, unsigned int n, unsigned int pos ) { char *endP = pMemory + fileSize; char *start = pMemory + pos; char *end = start + n; int i = 0; // Code to stay within your memory boundaries if( end &gt; endP ) { n -= (end - endP); // This might be wrong... end = endP; } if( end &lt; start ) return; // end boundary check for( ; start &lt; end; start++, i++ ) { buffer[i] = *start; } } </code></pre> <p>Here's the asm code generated from the code above by the compiler with -O2</p> <pre><code> .686P .XMM .model flat PUBLIC _readBytes _TEXT SEGMENT _fileSize$ = 8 ; size = 4 _pMemory$ = 12 ; size = 4 _buffer$ = 16 ; size = 4 _n$ = 20 ; size = 4 _pos$ = 24 ; size = 4 _readBytes PROC ; COMDAT mov eax, DWORD PTR _pMemory$[esp-4] mov edx, DWORD PTR _fileSize$[esp-4] mov ecx, DWORD PTR _n$[esp-4] add edx, eax add eax, DWORD PTR _pos$[esp-4] add ecx, eax cmp ecx, edx jbe SHORT $LN5@readBytes mov ecx, edx $LN5@readBytes: cmp eax, ecx jae SHORT $LN1@readBytes push esi mov esi, DWORD PTR _buffer$[esp] sub esi, eax $LL3@readBytes: mov dl, BYTE PTR [eax] mov BYTE PTR [esi+eax], dl inc eax cmp eax, ecx jb SHORT $LL3@readBytes pop esi $LN1@readBytes: ret 0 _readBytes ENDP _TEXT ENDS END </code></pre>
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    1. POAssembler + WinApi MapViewOfFile
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    1. USJimR
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Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

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