Copyright 1989 AT&T Copyright (c) 1996, Sun Microsystems, Inc. All Rights Reserved
The contents of this file are subject to the terms of the Common Development and Distribution License (the "License"). You may not use this file except in compliance with the License.
You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE or http://www.opensolaris.org/os/licensing. See the License for the specific language governing permissions and limitations under the License.
When distributing Covered Code, include this CDDL HEADER in each file and include the License file at usr/src/OPENSOLARIS.LICENSE. If applicable, add the following below this CDDL HEADER, with the fields enclosed by brackets "[]" replaced with your own identifying information: Portions Copyright [yyyy] [name of copyright owner]
cc [ flag ... ] file ... -lelf [ library ... ] #include <libelf.h> int elf_cntl(Elf *elf, Elf_Cmd cmd);
elf_cntl() instructs the library to modify its behavior with respect to an ELF descriptor, elf. As elf_begin(3ELF) describes, an ELF descriptor can have multiple activations, and multiple ELF descriptors may share a single file descriptor. Generally, elf_cntl() 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: ELF_C_FDDONE
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 elf_getdata() for a section, will fail if the data are not in memory already.
This command is similar to ELF_C_FDDONE, 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 elf_cntl() completes the ELF_C_FDREAD command, future operations, such as elf_getdata(), will use the memory version of the file without needing to use the file descriptor.
If elf_cntl() succeeds, it returns 0. Otherwise elf was NULL or an error occurred, and the function returns -1.
See attributes(7) for descriptions of the following attributes:
| ATTRIBUTE TYPE ATTRIBUTE VALUE |
| Interface Stability Stable |
| MT-Level MT-Safe |
elf (3ELF), elf_begin (3ELF), elf_getdata (3ELF), elf_rawfile (3ELF), libelf (3LIB), attributes (7)
If the program wishes to use the ``raw'' operations (see elf_rawdata(), which elf_getdata(3ELF) describes, and elf_rawfile(3ELF)) after disabling the file descriptor with ELF_C_FDDONE or ELF_C_FDREAD, it must execute the raw operations explicitly beforehand. Otherwise, the raw file operations will fail. Calling elf_rawfile() makes the entire image available, thus supporting subsequent elf_rawdata() calls.