elf_flagdata(3ELF) ELF Library Functions elf_flagdata(3ELF)NAME
elf_flagdata, elf_flagehdr, elf_flagelf, elf_flagphdr, elf_flagscn,
elf_flagshdr - manipulate flags
SYNOPSIS
cc [ flag ... ] file ... -lelf [ library ... ]
#include <libelf.h>
unsigned elf_flagdata(Elf_Data *data, Elf_Cmd cmd, unsigned flags);
unsigned elf_flagehdr(Elf *elf, Elf_Cmd cmd, unsigned flags);
unsigned elf_flagelf(Elf *elf, Elf_Cmd cmd, unsigned flags);
unsigned elf_flagphdr(Elf *elf, Elf_Cmd cmd, unsigned flags);
unsigned elf_flagscn(Elf_Scn *scn, Elf_Cmd cmd, unsigned flags);
unsigned elf_flagshdr(Elf_Scn *scn, Elf_Cmd cmd, unsigned flags);
DESCRIPTION
These functions manipulate the flags associated with various structures
of an ELF file. Given an ELF descriptor (elf), a data descriptor
(data), or a section descriptor (scn), the functions may set or clear
the associated status bits, returning the updated bits. A null descrip‐
tor is allowed, to simplify error handling; all functions return 0 for
this degenerate case.
cmd may have the following values:
ELF_C_CLR The functions clear the bits that are asserted in flags.
Only the non-zero bits in flags are cleared; zero bits do
not change the status of the descriptor.
ELF_C_SET The functions set the bits that are asserted in flags.
Only the non-zero bits in flags are set; zero bits do not
change the status of the descriptor.
Descriptions of the defined flags bits appear below:
ELF_F_DIRTY When the program intends to write an ELF file, this
flag asserts the associated information needs to be
written to the file. Thus, for example, a program that
wished to update the ELF header of an existing file
would call elf_flagehdr() with this bit set in flags
and cmd equal to ELF_C_SET. A later call to
elf_update() would write the marked header to the file.
ELF_F_LAYOUT Normally, the library decides how to arrange an output
file. That is, it automatically decides where to place
sections, how to align them in the file, etc. If this
bit is set for an ELF descriptor, the program assumes
responsibility for determining all file positions. This
bit is meaningful only for elf_flagelf() and applies to
the entire file associated with the descriptor.
When a flag bit is set for an item, it affects all the subitems as
well. Thus, for example, if the program sets the ELF_F_DIRTY bit with
elf_flagelf(), the entire logical file is ``dirty.''
EXAMPLES
Example 1 A sample display of calling the elf_flagdata() function.
The following fragment shows how one might mark the ELF header to be
written to the output file:
/* dirty ehdr ... */
ehdr = elf32_getehdr(elf);
elf_flagehdr(elf, ELF_C_SET, ELF_F_DIRTY);
ATTRIBUTES
See attributes(5) for descriptions of the following attributes:
┌─────────────────────────────┬─────────────────────────────┐
│ ATTRIBUTE TYPE │ ATTRIBUTE VALUE │
├─────────────────────────────┼─────────────────────────────┤
│Interface Stability │Committed │
├─────────────────────────────┼─────────────────────────────┤
│MT-Level │MT-Safe │
└─────────────────────────────┴─────────────────────────────┘
SEE ALSOelf(3ELF), elf32_getehdr(3ELF), elf_getdata(3ELF), elf_update(3ELF),
attributes(5)SunOS 5.10 11 Jul 2001 elf_flagdata(3ELF)