ELF32_GETPHDR(3ELF) ELF Library Functions ELF32_GETPHDR(3ELF)

NAME

elf32_getphdr, elf32_newphdr, elf64_getphdr, elf64_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);


Elf64_Phdr *elf64_getphdr(Elf *elf);


Elf64_Phdr *elf64_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_flagdata(3ELF). Specifying a zero count deletes an
existing table. Note this behavior differs from that of elf32_newehdr()
allowing a program to replace or delete the program header table,
changing its size if necessary. See elf32_getehdr(3ELF).


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 0.


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;


The Elf64_Phdr structures include 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;


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


The ELF header's e_phnum member tells how many entries the program header
table has. See elf32_getehdr(3ELF). 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.

ATTRIBUTES

See attributes(7) for descriptions of the following attributes:


+--------------------+-----------------+
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+--------------------+-----------------+
|Interface Stability | Stable |
+--------------------+-----------------+
|MT-Level | MT-Safe |
+--------------------+-----------------+

SEE ALSO

elf(3ELF), elf32_getehdr(3ELF), elf_begin(3ELF), elf_flagdata(3ELF),
libelf(3LIB), attributes(7)

July 11, 2001 ELF32_GETPHDR(3ELF)