/usr/include/emu/ is in libemu-dev 0.2.0+git20120122-1.2+b1.
This file is owned by root:root, with mode 0o755.
..
/usr/include/emu/emu.h
/usr/include/emu/emu_cpu.h
/usr/include/emu/emu_cpu_data.h
/usr/include/emu/emu_cpu_functions.h
/usr/include/emu/emu_cpu_instruction.h
/usr/include/emu/emu_cpu_itables.h
/usr/include/emu/emu_cpu_stack.h
/usr/include/emu/emu_fpu_instruction.h
/usr/include/emu/emu_getpc.h
/usr/include/emu/emu_graph.h
/usr/include/emu/emu_hashtable.h
/usr/include/emu/emu_instruction.h
/usr/include/emu/emu_list.h
/usr/include/emu/emu_log.h
/usr/include/emu/emu_memory.h
/usr/include/emu/emu_queue.h
/usr/include/emu/emu_shellcode.h
/usr/include/emu/emu_source.h
/usr/include/emu/emu_stack.h
/usr/include/emu/emu_string.h
/usr/include/emu/emu_track.h
/usr/include/emu/environment/
/usr/include/emu/environment/emu_env.h
/usr/include/emu/environment/emu_profile.h
/usr/include/emu/environment/linux/
/usr/include/emu/environment/linux/emu_env_linux.h
/usr/include/emu/environment/linux/env_linux_syscall_hooks.h
/usr/include/emu/environment/linux/env_linux_syscalls.h
/usr/include/emu/environment/win32/
/usr/include/emu/environment/win32/emu_env_w32.h
/usr/include/emu/environment/win32/emu_env_w32_dll.h
/usr/include/emu/environment/win32/emu_env_w32_dll_export.h
/usr/include/emu/environment/win32/env_w32_dll_export_hooks.h
/usr/include/emu/environment/win32/env_w32_dll_export_kernel32_hooks.h
/usr/include/emu/environment/win32/env_w32_dll_export_msvcrt_hooks.h
/usr/include/emu/environment/win32/env_w32_dll_export_shdocvw_hooks.h
/usr/include/emu/environment/win32/env_w32_dll_export_shell32_hooks.h
/usr/include/emu/environment/win32/env_w32_dll_export_urlmon_hooks.h
/usr/include/emu/environment/win32/env_w32_dll_export_ws2_32_hooks.h