Museum

Home

Lab Overview

Retrotechnology Articles

Online Manuals

⇒ filehdr(4) — DG/UX R4.11

Media Vault

Software Library

Restoration Projects

Artifacts Sought

Related Articles

time(2)

fseek(3S)

a.out(4)



filehdr(4)                       DG/UX R4.11                      filehdr(4)


NAME
       filehdr - file header for common object files

SYNOPSIS
       #include <filehdr.h>

DESCRIPTION
       Every common object file begins with a 20-byte header.  The following
       C struct declaration is used:

          struct  filehdr  {
             unsigned short  fmagic ;   /* magic number */
             unsigned short  fnscns ;   /* number of sections */
             long            ftimdat ;  /* time & date stamp */
             long            fsymptr ;  /* file ptr to symtab */
             long            fnsyms ;   /* # symtab entries */
             unsigned short  fopthdr ;  /* sizeof(opt hdr) */
             unsigned short  fflags ;   /* flags */
          } ;

       Fsymptr is the byte offset into the file at which the symbol table
       can be found.  Its value can be used as the offset in fseek(3S) to
       position an I/O stream to the symbol table.  The UNIX system optional
       header is 28-bytes.  The magic number for the M88000 is:

          #define MC88MAGIC 0540

       The value in ftimdat is obtained from the time(2) system call.  Flag
       bits currently defined are:

          #define FRELFLG  0000001 /* relocation entries stripped */
          #define FEXEC    0000002 /* file is executable */
          #define FLNNO    0000004 /* line numbers stripped */
          #define FLSYMS   0000010 /* local symbols stripped */
          #define FAR32W   0001000 /* non-DEC host */
          #define FBM32B   0020000 /* file contains WE 32100 code */
          #define FBM32MAU 0040000 /* file reqs MAU to execute */

SEE ALSO
       time(2), fseek(3S), a.out(4).


Licensed material--property of copyright holder(s)

Typewritten Software • bear@typewritten.org • Edmonds, WA 98026