3BSD/usr/include/a.out.h

/*
 * Format of an a.out header
 */
 
struct	exec {	/* a.out header */
	int		a_magic;	/* magic number */
	unsigned	a_text;		/* size of text segment */
	unsigned	a_data;		/* size of initialized data */
	unsigned	a_bss;		/* size of uninitialized data */
	unsigned	a_syms;		/* size of symbol table */
	unsigned	a_entry;	/* entry point */
	unsigned	a_trsize;	/* size of text relocation */
	unsigned	a_drsize;	/* size of data relocation */
};

#define	A_MAGIC1	0407		/* normal */
#define	A_MAGIC2	0410		/* read-only text */
#define	A_MAGIC3	0411		/* separated I&D (not on VAX) */
#define	A_MAGIC4	0405		/* overlay */
#define	A_MAGIC5	0413		/* demand page read-only text */

struct relocation_info {
	  long  r_address;	/* relative to current segment */
	  long	r_symbolnum:24,
				/* if extern then symbol table */
				/* ordinal (0, 1, 2, ...) else */
				/* segment number (same as symbol types) */
	        r_pcrel:1, 	/* if so, segment offset has already */
				/* been subtracted */
	  	r_length:2,	/* 0=byte, 1=word, 2=long */
	  	r_extern:1,	/* does not include value */
				/* of symbol referenced */
	  	r_offset:1,	/* already includes origin */
				/* of this segment (?) */
		r_pad:3;	/* nothing, yet */
};
struct	nlist { /* symbol table entry */
	char	n_name[8];	/* symbol name */
	char	n_type;		/* type flag */
	char	n_other;
	short	n_desc;
	unsigned n_value;	/* value */
};

	/* values for type flag */
#define	N_UNDF	0		/* undefined */
#define	N_ABS	02		/* absolute */
#define	N_TEXT	04		/* text */
#define	N_DATA	06		/* data */
#define	N_BSS	08
#define	N_TYPE	037
#define	N_FN	037		/* file name symbol */

#define	N_GSYM	0040		/* global sym: name,,type,0 */
#define	N_FNAME 0042		/* procedure name (f77 kludge): name,,,0 */
#define	N_FUN	0044		/* procedure: name,,linenumber,address */
#define	N_STSYM 0046		/* static symbol: name,,type,address */
#define	N_LCSYM 0048		/* .lcomm symbol: name,,type,address */
#define	N_RSYM	0100		/* register sym: name,,register,offset */
#define	N_SLINE	0104		/* src line: ,,linenumber,address */
#define	N_SSYM	0140		/* structure elt: name,,type,struct_offset */
#define	N_SO	0144		/* source file name: name,,,address */
#define	N_LSYM	0200		/* local sym: name,,type,offset */
#define	N_SOL	0204		/* #line source filename: name,,,address */
#define	N_PSYM	0240		/* parameter: name,,type,offset */
#define	N_ENTRY	0244		/* alternate entry: name,,linenumber,address */
#define	N_LBRAC	0300		/* left bracket: ,,nesting level,address */
#define	N_RBRAC	0340		/* right bracket: ,,nesting level,address */
#define N_BCOMM 0342		/* begin common: name,,, */
#define N_ECOMM 0344		/* end common: name,,, */
#define N_ECOML 0348		/* end common (local name): ,,,address */
#define	N_LENG	0376		/* second stab entry with length information */

#define	N_EXT	01		/* external bit, or'ed in */

#define	FORMAT	"%08x"

#define	STABTYPES	0340