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)

  —  ELF Library