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    <p>The standard <a href="http://linux.die.net/man/2/write" rel="nofollow noreferrer"><code>write</code></a> function accepts a <em>pointer</em> to what you want to write out; you're passing it a <code>char</code> (which is being promoted to an <code>int</code>).</p> <p>The minimal fix would be to change this:</p> <pre><code>write (socket, bmpheader[i], 1); </code></pre> <p>to</p> <pre><code>write (socket, &amp;bmpheader[i], 1); </code></pre> <p>...but there are better ways.</p> <p>You can just let <code>write</code> write out all 54 bytes itself:</p> <pre><code>write (socket, bmpheader, 54); </code></pre> <p>Or if you really want to do it a <code>char</code> at a time, you could use a pointer:</p> <pre><code>int i; char *p; for (i = 0, p = bmpheader; i &lt; 54; ++i, ++p) { printf("%c", *p); write (socket, p, 1); } </code></pre> <p>In either case, you want to avoid that magic number <code>54</code> and take it from the data. Since <code>sizeof(char)</code> is <a href="https://stackoverflow.com/questions/2215445/are-there-machines-where-sizeofchar-1">always one byte in standard C</a>, you can use <code>sizeof</code> without doing the ugly <code>sizeof(array) / sizeof(array[0])</code> thing:</p> <pre><code>int i; char *p; for (i = 0, p = bmpheader; i &lt; sizeof(bmpheader); ++i, ++p) { printf("%c", *p); write (socket, p, 1); } </code></pre> <p>...but I'm sure there's a more elegant solution than that.</p> <p>You can also use <code>putchar</code> (fairly lightweight) instead of <code>printf</code> (fairly heavyweight):</p> <pre><code>int i; char* p; for (i = 0, p = bmpheader; i &lt; sizeof(bmpheader); ++i, ++p) { putchar(*p); write (socket, p, 1); } </code></pre> <p>And I used to do things like this with pointer arithmetic, no idea whether they're bad practice in the modern world:</p> <pre><code>char* p; char* endp; for (p = bmpheader, p = bmpheader + sizeof(bmpheader); p &lt; endp; ++p) { putchar(*p); write (socket, p, 1); } </code></pre>
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    1. COAhh I knew there was some catch, didn't see the `&`. Thanks!
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    2. COSuper, thanks for the additional edit.
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    3. COWould the downvoter like to provide some useful feedback?
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