A/UX® Programmer's Reference Sections

scnhdr(4) scnhdr(4)
NAME
s cnhdr - section header for a common object file
SYNOPSIS
finclude
DESCRIPTION
Every common object file has a table of section headers to specify
the layout of the data within the file. Each section within an object
file has its own header. The C structure appears below.
struct scnhdr
{
char
long
long
long
long
long
long
unsigned short s_nreloc;
unsigned short s_nlnno;
s_name[SYMNMLEN]; 1* section name *1
s paddr; 1* physical address */
s=vaddr; 1* virtual address *1
s_size; 1* section size *1
s_scnptr; 1* file ptr to
raw data *1
s_relptr; 1* file ptr to
relocation */
s_lnnoptr; 1* file ptr to
line numbers *1
1* * reloc entries *1
1* * line number
entries *1
long 1* flags *1
File pointers are byte offsets into the file; they can be used as the
offset in a call to f seek(3S). If a section is initialized, the file
contains the actual bytes. An uninitialized section is somewhat
different. It has a size, symbols defined in it, and symbols that
refer to it, but it can have no relocation entries, line numbers, or
data. Consequently, an uninitialized section has no raw data in the
object file, and the values for s scnptr, s relptr,
s_lnnoptr, s_nreloc, and s_nlnno are zero. -
SEE ALSO
Id(I), fseek(3S), a. out(4).
1 February, 1990
RevisionC