Memory mapped files

void *mmap(void *addr, size_t len, int prot, int flags, int fd, off_t offset);

• Treat a file as if it were memory
• Map the file specified by fd to the virtual address adr
  • Changes are backed up to the file
• prot
  • specifies the protection of region
• flags
  • MAP_SHARED
    • Modifications seen by everyone
  • MAP_PRIVATE
    • Modifications are private
  • MAP_ANON
    • Anonymous memory