elf_open_read
struct elf *elf_open_read(const char *name, int flags);
e.orig = elf_open_read(argv[0], O_RDONLY);
e.patched = elf_open_read(argv[1], O_RDONLY);
elf = elf_open_read(argv[0], O_RDWR);
file.elf = elf_open_read(filename, O_RDWR);