text: // copy from https://github.com/klauspost/mman-win32
  /*
   * sys/mman.h
   * mman-win32
   */
  
  #ifndef _SYS_MMAN_H_
  #define _SYS_MMAN_H_
  
  #ifndef _WIN32_WINNT		// Allow use of features specific to Windows XP or later.                   
  #define _WIN32_WINNT 0x0501	// Change this to the appropriate value to target other versions of Windows.
  #endif						
  
  /* All the headers include this file. */
  #ifndef _MSC_VER
  #include <_mingw.h>
  #endif
  
  #include <sys/types.h>
  
  #ifdef __cplusplus
  extern "C" {
  #endif
  
  #define PROT_NONE       0
  #define PROT_READ       1
  #define PROT_WRITE      2
  #define PROT_EXEC       4
  
  #define MAP_FILE        0
  #define MAP_SHARED      1
  #define MAP_PRIVATE     2
  #define MAP_TYPE        0xf
  #define MAP_FIXED       0x10
  #define MAP_ANONYMOUS   0x20
  #define MAP_ANON        MAP_ANONYMOUS
  
  #define MAP_FAILED      ((void *)-1)
  
  /* Flags for msync. */
  #define MS_ASYNC        1
  #define MS_SYNC         2
  #define MS_INVALIDATE   4
  
  void*   mmap(void *addr, size_t len, int prot, int flags, int fildes, off_t off);
  int     munmap(void *addr, size_t len);
  int     mprotect(void *addr, size_t len, int prot);
  int     msync(void *addr, size_t len, int flags);
  int     mlock(const void *addr, size_t len);
  int     munlock(const void *addr, size_t len);
  
  #ifdef __cplusplus
  };
  #endif
  
  #endif /*  _SYS_MMAN_H_ */
  