xv6/elf.h

//
// format of an ELF executable file
//

#define ELF_MAGIC 0x464C457FU	/* "\x7FELF" in little endian */

struct elfhdr {
  uint magic;  // must equal ELF_MAGIC
  uchar elf[12];
  ushort type;
  ushort machine;
  uint version;
  uint entry;
  uint phoff;
  uint shoff;
  uint flags;
  ushort ehsize;
  ushort phentsize;
  ushort phnum;
  ushort shentsize;
  ushort shnum;
  ushort shstrndx;
};

struct proghdr {
  uint type;
  uint offset;
  uint va;
  uint pa;
  uint filesz;
  uint memsz;
  uint flags;
  uint align;
};

// Values for Proghdr type
#define ELF_PROG_LOAD		1

// Flag bits for Proghdr flags
#define ELF_PROG_FLAG_EXEC	1
#define ELF_PROG_FLAG_WRITE	2
#define ELF_PROG_FLAG_READ	4