elf_cntl(3E)elf_cntl(3E)NAMEelf_cntl - control a file descriptor
SYNOPSIS
[flag... ] file... [library] ...
DESCRIPTION
instructs the library to modify its behavior with respect to an ELF
descriptor, elf. As elf_begin(3E) describes, an ELF descriptor can
have multiple activations, and multiple ELF descriptors may share a
single file descriptor. Generally, commands apply to all activations
of elf. Moreover, if the ELF descriptor is associated with an archive
file, descriptors for members within the archive will also be affected
as described below. Unless stated otherwise, operations on archive
members do not affect the descriptor for the containing archive.
The cmd argument tells what actions to take and may have the following
values.
This value tells the library not to use the file
descriptor associated with elf. A program should use
this command when it has requested all the informa‐
tion it cares to use and wishes to avoid the overhead
of reading the rest of the file. The memory for all
completed operations remains valid, but later file
operations, such as the initial for a section, will
fail if the data is not in memory already.
This command is similar to
except it forces the library to read the rest of the
file. A program should use this command when it must
close the file descriptor but has not yet read every‐
thing it needs from the file. After completes the
command, future operations, such as will use the mem‐
ory version of the file without needing to use the
file descriptor.
If succeeds, it returns zero. Otherwise, elf was null or an error
occurred, and the function returns -1.
Note
If the program wishes to use the ``raw'' operations (see described in
elf_getdata(3E), and elf_rawfile(3E)) after disabling the file descrip‐
tor with or it must execute the raw operations explicitly beforehand.
Otherwise, the raw file operations will fail. Calling makes the entire
image available, thus supporting subsequent calls.
SEE ALSOelf(3E), elf_begin(3E), elf_getdata(3E), elf_rawfile(3E).
elf_cntl(3E)