ELF_GETEHDR(3E)ELF_GETEHDR(3E)NAME
elf_getehdr: 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 elf_getehdr),
one cannot be created (for elf_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 64-bit class files, the 64 version is applicable instead of the 32
version of the functions.
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;
For 64-bit class files, the following is applicable.
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ELF_GETEHDR(3E)ELF_GETEHDR(3E)
unsigned char e_ident[EI_NIDENT];
Elf64_Half e_type;
Elf64_Half e_machine;
Elf64_Word e_version;
Elf64_Addr e_entry;
Elf64_Off e_phoff;
Elf64_Off e_shoff;
Elf64_Word e_flags;
Elf64_Half e_ehsize;
Elf64_Half e_phentsize;
Elf64_Half e_phnum;
Elf64_Half e_shentsize;
Elf64_Half e_shnum;
Elf64_Half e_shstrndx;
elf32_newehdr automatically sets the ELF_F_DIRTY bit [see elf_flag(3E)].
A program may use elf_getident to inspect the identification bytes from a
file.
The 64-bit class works identically, simply replacing all instances of 32
in the description with 64.
SEE ALSOelf(3E), elf_begin(3E), elf_flag(3E), elf_getident(3E).
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