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POc++ unsigned char memory copy
 

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    <p>I need to pass an unsigned char array from one method to another, and i tried using this code:</p> <pre><code>{ unsigned char *lpBuffer = new unsigned char[182]; ReceiveSystemState(lpBuffer); } BOOL ReceiveSystemState(unsigned char *lpBuffer) { unsigned char strRecvBuffer[182] = { 0 }; //strRecvBuffer construction memcpy(lpBuffer, strRecvBuffer, sizeof(strRecvBuffer)); return TRUE; } </code></pre> <p>Neither of those 3 methods (used in <code>ReceiveSystemState</code>) worked as i expected. After using each one of them all that it is copied is the first char from <code>strRecvBuffer</code> and nothing more. The <code>strRecvBuffer</code> has empty chars from element to element, but i need those as they are, because that string is a message from a hardware device and that message will be anallysed using a protocol. What do i miss here? Do i initialize <code>lpBuffer</code> wrong?</p> <p>EDIT: I've used a simple <code>memcpy</code> method to do the job. Still the same result: all that it is copied is the first char of <code>strRecvBuffer</code>.</p> <p>EDIT2: Working code:</p> <pre><code>{ unsigned char *lpBuffer = new unsigned char[182]; ReceiveSystemState(lpBuffer); for (int i = 0; i &lt; 144; i++) { memcpy(&amp;c_dateKG[i], lpBuffer + i * sizeof(unsigned char), sizeof(unsigned char) ); } } BOOL ReceiveSystemState(unsigned char *lpBuffer) { unsigned char strRecvBuffer[182] = { 0 }; //strRecvBuffer construction memcpy(lpBuffer, strRecvBuffer, sizeof(strRecvBuffer)); return TRUE; } </code></pre>
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    1. CO@Nobody...I don't think it will make a difference since `unsigned char` has 1 byte size. so basically `182 * sizeof(unsigned char)` is same as `182`.
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    2. COI don't get this. Where should that data come from? You define strRecvBuffer to contain one 0 and garbage after that. Other than that, memcpy will copy all of the array, as will your loop.
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    3. CO`= { 0 }` is the syntax to set all elements to 0
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