AT&T UNIX™PC Unix System V Users Manual - tenox

A.OUT ( 4) A.OUT (4)
} AOUTHDR;
Section Header
The format of the section header is:
struct scnhdr
{
};
char
long
long
long
long
long
long
unsigned short
unsigned short
long
s_name[SYMNMLEN] ;I* section name *I
s_paddr; I* physical address *I
s_ vaddr; I* virtual address *I
s_size; I* section size *I
s_scnptr; I* file ptr to raw data *I
s_relptr; I* file ptr to relocation *I
s_lnnoptr; I* file ptr to line numbers *I
s_nreloc; I* # reloc entries *I
s_nlnno; I* # line number entries *I
s_flags; I* flags *I
Relocation
Object files have one relocation entry for each relocatable reference
in the text or data. If relocation information is present, it
will be in the following format:
struct reloc
{
};
long
long
short
r_vaddr; I* (virtual) address of reference *I
r_symndx; I* index into symbol table *I
r_type; I* relocation type *I
The start of the relocation information is s_relptr from the Section
Header. If there is no relocation information, s_relptr is 0.
Symbol Table
The format of the symbol table header is:
#define SYMNMLEN 8
#define FILNMLEN 14
#define SYMESZ 18 I* the size of a SYMENT *I
struct syment
{
union
{
}_n;
I* get a symbol name *I
char n_name]SYMNMLEN];I* name of symbol *I
struct
{
long
long
}_n_n;
char
unsigned long
short
unsigned short
char
_n_zeroes;
_n_offset;
I* ==OL if in string table *I
I* location in string table *I
* _n_nptr]2]; I* allows overlaying *I
n_value;
n_scnum;
n_type;
n_sclass;
- 3 -
I* value of symbol *I
I* section number *I
I* type and derived type *I
I* storage class *I