Page 1                                        (last mod. 8/20/87)

     FILEHDR(4)                                             FILEHDR(4)



     NAME
          filehdr - file header for MIPS object files

     SYNOPSIS
          #include < filehdr.h>

     DESCRIPTION
          Every MIPS 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 */
          };

          F_symptr is the byte offset into the file at which the
          symbolic header can be found.  Its value can be used as the
          offset in fseek(3S) to position an I/O stream to the
          symbolic header.  The UMIPS system optional header is 56-
          bytes.  The valid magic numbers are given below:
          #define  MIPSEBMAGIC  0x0160  /* objects for MIPS big-endian machines */
          #define  MIPSELMAGIC  0x0162  /* objects for MIPS little-endian machines */
          #define  MIPSEBUMAGIC  0x0180  /* ucode objects for MIPS*/
                                        /* big-endian machines */
          #define  MIPSELUMAGIC  0x0182  /* ucode objects for MIPS*/
                                        /* little-endian machines */

          MIPS 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  time(2)  system
          call.  Flag bits used in MIPS 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(4).

     ORIGIN



     Page 1                                        (last mod. 8/20/87)

     FILEHDR(4)                                             FILEHDR(4)



          MIPS Computer Systems






















































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