elf_rand(3E)

NAME
     elf_rand - random archive member access

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

     #include <libelf.h>
     size_t elf_rand(Elf *elf, size_t offset);

DESCRIPTION
     elf_rand, elf_next, and elf_begin manipulate simple object files and
     archives.  elf is an ELF descriptor previously returned from elf_begin.

     elf_rand 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 elf_getarsym(3E) for more information about archive member
     offsets.  When elf_rand 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 (elf_rand(elf, (size_t)SARMAG) == SARMAG)
                          return 0;
                  return -1;
          }

SEE ALSO
     elf(3E), elf_begin(3E), elf_getarsym(3E), elf_next(3E), ar(4).