ultrix man page for filehdr

filehdr(5)							File Formats Manual							filehdr(5)

Name
       filehdr - file header for RISC object files

Syntax
       #include < filehdr.h>

Description
       Every RISC object file begins with a 20-byte header.  The following C struct declaration is used:
       struct filehdr
       {
	  unsigned short  f_magic;     /* magic number */
	  unsigned short  f_nscns;     /* number of sections */
	  long		  f_timdat;    /* time & date stamp */
	  long		  f_symptr;    /* file pointer to symbolic header */
	  long		  f_nsyms;     /* sizeof(symbolic header) */
	  unsigned short  f_opthdr;    /* sizeof(optional header) */
	  unsigned short  f_flags;     /* flags */
       };

       The byte offset into the file at which the symbolic header can be found is f_symptr.  Its value can be used as the offset in to position an
       I/O stream to the symbolic header.  The ULTRIX system optional header is 56 bytes.  The valid magic numbers are given below:
       #define MIPSEBMAGIC 0x0160 /* objects for big-endian machines */
       #define MIPSELMAGIC 0x0162 /* objects for little-endian machines */
       #define MIPSEBUMAGIC 0x0180 /* ucode objects for big-endian machines */
       #define MIPSELUMAGIC 0x0182 /* ucode objects for little-endian machines */
       RISC object files can be loaded and examined on machines differing from the object's target byte sex.  Therefore,  for  object  file  magic
       numbers, the byte-swapped values have define constants associated with them:
       #define SMIPSEBMAGIC 0x6001
       #define SMIPSELMAGIC 0x6201
       The value in f_timdat is obtained from the system call.	Flag bits used in RISC objects are:
       #define F_RELFLG 0000001  /* relocation entries stripped */
       #define F_EXEC	0000002  /* file is executable */
       #define F_LNNO	0000004  /* line numbers stripped */
       #define F_LSYMS	0000010  /* local symbols stripped */

See Also
       time(2), fseek(3s), a.out(5)

								       RISC								filehdr(5)