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copied!<p>Does it specifically need to call the Lua standard library <code>print</code> function? Can you instead emulate the functionality of <code>print</code>? Because that would be the easiest way.</p> <p>However, if you want to have a wrapper around <code>print</code>, there are two ways to do it: with pure Lua code, and with C/C++ code.</p> <p>The pure Lua solution is as follows. Note that this should be done before loading any external scripts. First, open the Lua standard library that has <code>print</code> in it. Then run this Lua script:</p> <pre><code>local internal_print = print return function(...) --Do display logic. internal_print(...) --Or whatever else you want. end </code></pre> <p>This will return the "display" function. You can store it in a global variable called <code>display</code> if you like, or called something else.</p> <p>After that, you can <code>nil</code> out the <code>print</code> global variable, thus making it almost entirely inaccessible.</p> <p>If you want to do it from C/C++, it's very similar. First, as before, you register the Lua standard library that includes <code>print</code>, so that you can get the function for it. Then, you use <code>lua_getglobal(L, "print")</code> to get the <code>print</code> function and push it onto the stack. Next, you register your C/C++ function using using <code>lua_pushcclosure</code>. But you want to specify one upvalue, which Lua pops off the stack at registration time.</p> <p>And now your registered function is on the stack, waiting to be pushed into a Lua variable or global table entry.</p> <p><strong>Warning:</strong> the Lua debug library can poke at upvalues and thus get the <code>print</code> function from your new function. So if you want perfect security, get rid of <code>debug.getupvalue</code>.</p>

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