1.2 How To Use BFD

To use the library, include bfd.h and link with libbfd.a.

BFD provides a common interface to the parts of an object file for a calling application.

When an application successfully opens a target file (object, archive, or whatever), a pointer to an internal structure is returned. This pointer points to a structure called bfd, described in bfd.h. Our convention is to call this pointer a BFD, and instances of it within code abfd. All operations on the target object file are applied as methods to the BFD. The mapping is defined within bfd.h in a set of macros, all beginning with ‘bfd_’ to reduce namespace pollution.

For example, this sequence does what you would probably expect: return the number of sections in an object file attached to a BFD abfd.

     
     #include "bfd.h"
     
     unsigned int number_of_sections (abfd)
     bfd *abfd;
     {
       return bfd_count_sections (abfd);
     }
     

The abstraction used within BFD is that an object file has:

• a header,
• a number of sections containing raw data (see Sections),
• a set of relocations (see Relocations), and
• some symbol information (see Symbols).