elf_cntl(3E) elf_cntl(3E)
NAME
elf_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 ar-
chive.
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 information 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 everything it needs from the file. After completes the command, future operations, such
as will use the memory 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
descriptor 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 ALSO
elf(3E), elf_begin(3E), elf_getdata(3E), elf_rawfile(3E).
elf_cntl(3E)
