메모리맵

/usr/include/asm/a.out.h라는 파일에 그 구조가 있습니다.
간단하게 옮기면

struct exec
{
  unsigned long a_info;         /* Use macros N_MAGIC, etc for access */
  unsigned a_text;              /* length of text, in bytes */
  unsigned a_data;              /* length of data, in bytes */
  unsigned a_bss;               /* length of uninitialized data area for file, in bytes */
  unsigned a_syms;              /* length of symbol table data in file, in bytes */
  unsigned a_entry;             /* start address */
  unsigned a_trsize;            /* length of relocation info for text, in bytes */
  unsigned a_drsize;            /* length of relocation info for data, in bytes */
};