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    copied!<p>You call GetStdHandle and save the returned value to ecx, ecx is a volatile register, the value will not be saved across calls unless you push/pop it. Your first call to WriteConsoleA uses it and clobbers it so the next call, ecx is not what you expect.</p> <p><strong>* EDIT *</strong> I was bored so here is working code:</p> <pre><code>[bits 32] section .data program db "Program: ", 0 programlen equ $-program nl db "", 13, 10, 0 nllen equ $-nl section .bss buf resd 1 argc resd 1 argv resb 255 section .text global Start extern GetStdHandle extern __getmainargs extern WriteConsoleA extern ExitProcess strlen: ; eax: a string ending in 0 push eax ; cache eax .strloop: mov bl, byte [eax] cmp bl, 0 je .strret ; return len if bl == 0 inc eax ; else eax++ jmp .strloop .strret: pop ebx ; ebx = cached eax sub eax, ebx ; eax -= ebx ret ; eax = len Start: push 0 push buf push argv push argc call __getmainargs add esp, 16 ; clear stack (4 * 4 arguments) push -11 ; get stdout call GetStdHandle mov esi, eax add esp, 4 ; clear stack (4 * 1 argument) push 0 ; null push buf ; [chars written] push programlen push program push esi ; stdout call WriteConsoleA add esp, 20 ; clear stack (4 * 5 arguments) mov edx, [argv] mov eax, [edx] ; &lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt; call strlen push 0 ; null push buf ; [chars written] push eax ; len argv[0] push dword [edx] ;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt; ; argv[0] push esi ; stdout call WriteConsoleA add esp, 20 ; clear stack (4 * 5 arguments) push 0 ; null push buf ; [chars written] push nllen push nl push esi ; stdout call WriteConsoleA add esp, 20 ; clear stack (4 * 5 arguments) push 0 call ExitProcess D:\NASM Projects\ReadArgs&gt;ReadArgs.exe Program: ReadArgs.exe D:\NASM Projects\ReadArgs&gt; </code></pre>
 

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