Fix calling convention and return value #28
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System V x86-64 ABI System Call calling convention for param3 is r10 while Userspace calling convention for param3 is rcx. Actually, rdx:rax are used to return 128 bit value or edx:eax are used to return 64 bit value. Ref : man syscall and System V ABI docs
Fix calling convention and return value
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System Call calling convention on System V x86-64 parameter is r10 while the usespace function calling convention is rcx.
Actually, Linux system call is return 128 bit (x86-64), 64 bit (i386) value.
RDX as upper bits and EDX as upper bits. They're not changed if the value if rax / eax is enough to hold the return value.