LINENUM(4)                           SysV                           LINENUM(4)



NAME
     linenum - line number entries in a common object file

SYNOPSIS
     #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(1)).  Users can then reference line numbers when using the
     appropriate software test system.  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 nonzero,
     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(1), a.out(4).