LINENUM(F)                                 UNIX System V



     Name
          linenum - line number entries in a common object file


     Syntax
          #include  <linenum.h>


     Description
          The cc command generates an entry in  the  object  file  for
          each  C  source line on which a breakpoint is possible [when
          invoked with the -g option; see  cc(CP)].   Users  can  then
          reference  line  numbers when using the appropriate software
          test system [see sdb(CP)].   The  structure  of  these  line
          number entries appears below.

          struct  lineno
          {
                  union
                  {
                         long     l_symndx ;
                         long     l_paddr ;
                  }               l_addr ;
                  unsigned short  l_lnno ;
          } ;

          Numbering starts with one for each  function.   The  initial
          line  number  entry for a function has l_lnno equal to zero,
          and the symbol table index of the  function's  entry  is  in
          l_symndx.  Otherwise, l_lnno is non-zero, and l_paddr is the
          physical address of the code for the referenced line.   Thus
          the overall structure is the following:

          l_addr                   l_lnno

          function symtab index    0
          physical address         line
          physical address         line
          ...

          function symtab index    0
          physical address         line
          physical address         line
          ...



     See Also
          cc(CP), sdb(CP), a.out(F)


     (printed 8/23/89)                                  LINENUM(F)