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ELF_GETSCN(3) FreeBSD Library Functions Manual ELF_GETSCN(3)
NAME
elf_getscn, elf_ndxscn, elf_newscn, elf_nextscn - get/allocate section
information for an ELF object
LIBRARY
ELF Access Library (libelf, -lelf)
SYNOPSIS
#include <libelf.h>
Elf_Scn *
elf_getscn(Elf *elf, size_t index);
size_t
elf_ndxscn(Elf_Scn *scn);
Elf_Scn *
elf_newscn(Elf *elf);
Elf_Scn *
elf_nextscn(Elf *elf, Elf_Scn *scn);
DESCRIPTION
These functions are used to iterate through the sections associated with
an ELF descriptor.
Function elf_getscn() will return a section descriptor for the section at
index index in the object denoted by ELF descriptor elf. An error will
be signalled if the specified section does not exist.
Function elf_ndxscn() returns the section table index associated with
section descriptor scn.
Function elf_newscn() creates a new section and appends it to the list of
sections associated with descriptor elf. The library will automatically
increment the e_shnum field of the ELF header associated with descriptor
elf, and will set the ELF_F_DIRTY flag on the returned section
descriptor. For ELF descriptors opened for writing, the ELF library will
automatically create an empty section at index zero (SHN_UNDEF) on the
first call to elf_newscn().
Function elf_nextscn() takes a section descriptor scn and returns a
pointer to the section descriptor at the next higher index. As a
consequence, elf_nextscn() will never return a pointer to the empty
section at index zero (SHN_UNDEF). Argument scn is allowed to be NULL,
in which case this function will return a pointer to the section
descriptor at index 1. If no further sections are present, function
elf_nextscn() will return a NULL pointer.
RETURN VALUES
Functions elf_getscn(), elf_newscn() and elf_nextscn() return a valid
pointer to a section descriptor if successful, or NULL if an error
occurs.
Function elf_ndxscn() returns a valid section table index if successful,
or SHN_UNDEF if an error occurs.
[ELF_E_ARGUMENT] Argument elf was not a descriptor for an ELF file.
[ELF_E_ARGUMENT] Section descriptor scn was not associated with ELF
descriptor elf.
[ELF_E_CLASS] Descriptor elf was of an unknown ELF class.
[ELF_E_SECTION] Argument elf specified extended section numbering in
the ELF header with the section header at index
SHN_UNDEF not being of type SHT_NULL.
SEE ALSO
elf(3), elf_flagdata(3), elf_flagscn(3), elf_getdata(3), elf_getshdr(3),
gelf(3)
FreeBSD 14.0-RELEASE-p11 September 24, 2018 FreeBSD 14.0-RELEASE-p11