elf32_getehdr

, elf32_newehdr

, elf64_getehdr

, elf64_newehdr

- retrieve class-dependent object file header

Synopsis

cc [ flag ... ] file ... -lelf [ library ... ]
#include <libelf.h>

Elf32_Ehdr *elf32_getehdr(Elf *elf);

Elf32_Ehdr *elf32_newehdr(Elf *elf);

Elf64_Ehdr *elf64_getehdr(Elf *elf);

Elf64_Ehdr *elf64_newehdr(Elf *elf);

Description

For a 32-bit class file, elf32_getehdr() returns a pointer to an ELF header, if one is available for the ELF descriptor elf. If no header exists for the descriptor, elf32_newehdr() allocates a clean one, but it otherwise behaves the same as elf32_getehdr(). It does not allocate a new header if one exists already. If no header exists for elf32_getehdr(), one cannot be created for elf32_newehdr(), a system error occurs, the file is not a 32-bit class file, or elf is NULL, both functions return a null pointer.

For the 64-bit class, replace 32 with 64 as appropriate.

The header includes the following members:

unsigned char    e_ident[EI_NIDENT];
Elf32_Half    e_type;
Elf32_Half    e_machine;
Elf32_Word    e_version;
Elf32_Addr    e_entry;
Elf32_Off     e_phoff;
Elf32_Off     e_shoff;
Elf32_Word    e_flags;
Elf32_Half    e_ehsize;
Elf32_Half    e_phentsize;
Elf32_Half    e_phnum;
Elf32_Half    e_shentsize;
Elf32_Half    e_shnum;
Elf32_Half    e_shstrndx;

The elf32_newehdr() function automatically sets the ELF_F_DIRTY bit. See elf_flagdata(3ELF).

An application can use elf_getident() to inspect the identification bytes from a file.

An application can use elf_getshnum() and elf_getshstrndx() to obtain section header information. The location of this section header information differs between standard ELF files to those that require Extended Sections.

Attributes

See attributes(5) for descriptions of the following attributes:

See Also

elf(3ELF), elf_begin(3ELF), elf_flagdata(3ELF), elf_getident(3ELF), elf_getshnum(3ELF), elf_getshstrndx(3ELF), libelf(3LIB), attributes(5)