elf_getphdr: elf32_getphdr, elf32_newphdr, elf64_getphdr, elf64_newphdr -- retrieve class-dependent program header table


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

#include <libelf.h>

Elf32_Phdr *elf32_getphdr(Elf *elf);

Elf32_Phdr *elf32_newphdr(Elf *elf, size_t count);

Elf64_Phdr *elf64_getphdr(Elf *elf);

Elf64_Phdr *elf64_newphdr(Elf *elf, size_t count);


For a 32-bit class file, elf32_getphdr returns a pointer to the program execution header table, if one is available for the ELF descriptor elf.

elf32_newphdr allocates a new table with count entries, regardless of whether one existed previously, and sets the ELF_F_DIRTY bit for the table [see elf_flag(3elf)]. Specifying a zero count deletes an existing table. Note this behavior differs from that of elf32_newehdr [see elf_getehdr(3elf)], allowing a program to replace or delete the program header table, changing its size if necessary.

If no program header table exists, the file is not a 32-bit class file, an error occurs, or elf is null, both functions return a null pointer. Additionally, elf32_newphdr returns a null pointer if count is zero.

The table is an array of Elf32_Phdr structures, each of which includes the following members.

Elf32_Word p_type; Elf32_Off p_offset; Elf32_Addr p_vaddr; Elf32_Addr p_paddr; Elf32_Word p_filesz; Elf32_Word p_memsz; Elf32_Word p_flags; Elf32_Word p_align;
elf64_getphdr and elf64_newhdr provide the same functionality for 64-bit class files. The table is an array of Elf64_Phdr structures, each of which includes the following members.

Elf64_Word p_type; Elf64_Word p_flags; Elf64_Off p_offset; Elf64_Addr p_vaddr; Elf64_Addr p_paddr; Elf64_Xword p_filesz; Elf64_Xword p_memsz; Elf64_Xword p_align;

The ELF header's e_phnum member tells how many entries the program header table has [see elf_getehdr(3elf)]. A program may inspect this value to determine the size of an existing table; elf32_newphdr and elf64_newphdr automatically set the member's value to count. If the program is building a new file, it is responsible for creating the file's ELF header before creating the program header table.


Intro(3elf), elf_begin(3elf), elf_flag(3elf), elf_getehdr(3elf)
© 2004 The SCO Group, Inc. All rights reserved.
UnixWare 7 Release 7.1.4 - 25 April 2004