NAME

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

SYNOPSIS

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

#include <libelf.h>
Elf32_Phdr ∗elf32_getphdr(Elf ∗elf);
Elf32_Phdr ∗elf32_newphdr(Elf ∗elf, size_t count);

DESCRIPTION

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(3E)].  Specifying a zero count deletes an existing table.  Note this behavior differs from that of elf32_newehdr [see elf32_getehdr(3E)], 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_Wordp_type;
Elf32_Offp_offset;
Elf32_Addrp_vaddr;
Elf32_Addrp_paddr;
Elf32_Wordp_filesz;
Elf32_Wordp_memsz;
Elf32_Wordp_flags;
Elf32_Wordp_align;

The ELF header’s e_phnum member tells how many entries the program header table has [see elf_getehdr(3E)].  A program may inspect this value to determine the size of an existing table; elf32_newphdr automatically sets 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. 

SEE ALSO

elf(3E), elf_begin(3E), elf_flag(3E), elf_getehdr(3E)

  —  ELF Library