elf_rand(3E)                   (ELF Library)                   elf_rand(3E)


   NAME
         elfrand - random archive member access

   SYNOPSIS
         cc [flag ...] file ...  -lelf [library ...]

         #include <libelf.h>
         sizet elfrand(Elf *elf, sizet offset);

   DESCRIPTION
         elfrand, elfnext, and elfbegin manipulate simple object files and
         archives.  elf is an ELF descriptor previously returned from
         elfbegin.

         elfrand provides random archive processing, preparing elf to access
         an arbitrary archive member.  elf must be a descriptor for the
         archive itself, not a member within the archive.  offset gives the
         byte offset from the beginning of the archive to the archive header
         of the desired member.  See elfgetarsym(3E) for more information
         about archive member offsets.  When elfrand works, it returns
         offset.  Otherwise it returns 0, because an error occurred, elf was
         null, or the file was not an archive (no archive member can have a
         zero offset).  A program may mix random and sequential archive
         processing.

   EXAMPLE
         An archive starts with a ``magic string'' that has SARMAG bytes; the
         initial archive member follows immediately.  An application could
         thus provide the following function to rewind an archive (the
         function returns -1 for errors and 0 otherwise).

              #include <ar.h>
              #include <libelf.h>

              int
              rewindelf(Elf *elf)
              {
                      if (elfrand(elf, (sizet)SARMAG) == SARMAG)
                              return 0;
                      return -1;
              }

   SEE ALSO
         elf(3E), elfbegin(3E), elfgetarsym(3E), elfnext(3E), ar(4).









   7/91                                                                 Page 1