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GNU Binary Utilities
The GNU Binary Utilities, or , are a set of programming tools for creating and managing binary programs, object files, libraries, profile data, and assembly source code. Tools They were originally written by programmers at Cygnus Solutions. The GNU Binutils are typically used in conjunction with compilers such as the GNU Compiler Collection (), build tools like , and the GNU Debugger (). Through the use of the Binary File Descriptor library (), most tools support the various object file formats supported by . Commands The include the following commands: elfutils Ulrich Drepper wrote , to partially replace GNU Binutils, purely for Linux and with support only for ELF and DWARF. It distributes three libraries with it for programmatic access. See also * GNU Core Utilities * GNU Debugger *ldd (Unix), list symbols imported by the object file; similar to * List of Unix commands *llvm provides similar set of tools * strace strace is a diagnostic, debugging and instructi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
GNU Project
The GNU Project () is a free software, mass collaboration project announced by Richard Stallman on September 27, 1983. Its goal is to give computer users freedom and control in their use of their computers and computing devices by collaboratively developing and publishing software that gives everyone the rights to freely run the software, copy and distribute it, study it, and modify it. GNU software grants these rights in its license. In order to ensure that the ''entire'' software of a computer grants its users all freedom rights (use, share, study, modify), even the most fundamental and important part, the operating system (including all its numerous utility programs) needed to be free software. According to its manifesto, the founding goal of the project was to build a free operating system, and if possible, "everything useful that normally comes with a Unix system so that one could get along without any software that is not free." Stallman decided to call this operating ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Profiling (computer Programming)
In software engineering, profiling ("program profiling", "software profiling") is a form of dynamic program analysis that measures, for example, the space (memory) or time complexity of a program, the usage of particular instructions, or the frequency and duration of function calls. Most commonly, profiling information serves to aid program optimization, and more specifically, performance engineering. Profiling is achieved by instrumenting either the program source code or its binary executable form using a tool called a ''profiler'' (or ''code profiler''). Profilers may use a number of different techniques, such as event-based, statistical, instrumented, and simulation methods. Gathering program events Profilers use a wide variety of techniques to collect data, including hardware interrupts, code instrumentation, instruction set simulation, operating system hooks, and performance counters. Use of profilers The output of a profiler may be: * A statistical ''s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Strings (Unix)
In computer software, strings is a program in Unix, Plan 9, Inferno, and Unix-like operating systems that finds and prints text strings embedded in binary files such as executables. It can be used on object files and core dumps. Overview Strings are recognized by looking for sequences of at least 4 (by default) printable characters terminating in a NUL character (that is, null-terminated strings). Some implementations provide options for determining what is recognized as a printable character, which is useful for finding non-ASCII and wide character text. Common usage includes piping its output to and or redirecting the output to a file. It is part of the GNU Binary Utilities (), and has been ported to other operating systems including Windows.cygwin Example Using ''strings'' to print sequences of characters that are at least 8 characters long (this command prints the system's BIOS information; should be run as root): dd if=/dev/mem bs=1k skip=768 count=256 2>/dev/null , ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Readelf
readelf is a program for displaying various information about object files on Unix-like systems such as objdump. It is part of the GNU binutils. readelf and objdump objdump has a similar function but with different features like disassembling. The main difference is that readelf does not depend on BFD and helps to check if BFD works. Example The following command displays the contents of the file's dynamic section (to examine the shared library dependencies and rpath rPath, Inc. was a technology company based in Raleigh, North Carolina that developed technology to automate the process of constructing (or packaging), deploying and updating software.Craig, Julie. "Cloud Coalition: rPath, newScale, and Eucalyp ...): $ readelf -d References Unix programming tools GNU Project software {{unix-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ranlib
The archiver, also known simply as ar, is a Unix utility that maintains groups of files as a single archive file. Today, ar is generally used only to create and update static library files that the link editor or linker uses and for generating .deb packages for the Debian family; it can be used to create archives for any purpose, but has been largely replaced by tar for purposes other than static libraries. An implementation of ar is included as one of the GNU Binutils. In the Linux Standard Base (LSB), ar has been deprecated and is expected to disappear in a future release of that standard. The rationale provided was that "the LSB does not include software development utilities nor does it specify .o and .a file formats." File format details The ar format has never been standardized; modern archives are based on a common format with two main variants, BSD and System V (initially known as COFF, and used as well by GNU, ELF, and Windows.) Historically there have been other v ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Objdump
objdump is a command-line program for displaying various information about object files on Unix-like operating systems. For instance, it can be used as a disassembler to view an executable in assembly form. It is part of the GNU Binutils for fine-grained control over executables and other binary data. objdump uses the BFD library to read the contents of object files. Similar utilities are Borland TDUMP, Microsoft DUMPBIN and readelf. Note that on certain platforms (e.g. macOS), the objdump binary may actually be a link to llvm's objdump, with different command-line options and behavior. Example For example, $ objdump -D -M intel file.bin , grep main.: -A20 This performs disassembly on the file «file.bin», with the assembly code shown in Intel syntax. We then redirect it to grep, which searches the main function and displays 20 lines of its code. Example output: 4004ed: 55 push rbp 4004ee: 48 89 e5 mov rbp,rsp 4004f1: c7 45 ec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nm (Unix)
nm (name mangling) is a Unix command used to dump the symbol table and their attributes from a binary executable file (including libraries, compiled object modules, shared-object files, and standalone executables). The output from nm distinguishes between various symbol types. For example, it differentiates between a function that is supplied by an object module and a function that is required by it. nm is used as an aid for debugging, to help resolve problems arising from name conflicts and C++ name mangling, and to validate other parts of the toolchain. This command is shipped with a number of later versions of Unix and similar operating systems including Plan 9. The GNU Project ships an implementation of nm as part of the GNU Binutils package. nm output sample /* * File name: test.c * For C code compile with: * gcc -c test.c * * For C++ code compile with: * g++ -c test.cpp */ int global_var; int global_var_init = 26; static int static_var; static int static_ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
NetWare Loadable Module
A NetWare Loadable Module (NLM) is a loadable kernel module (a binary code module) that can be loaded into Novell's NetWare operating system. NLMs can implement hardware drivers, server functions (e.g. clustering), applications (e.g. GroupWise), system libraries or utilities. NLMs were supported beginning with the Intel 80386-based NetWare version 3.x. Prior versions of NetWare had a monolithic kernel, and significant hardware or functionality changes required re-linking the kernel from object modules. Due to stability issues with early third-party NLMs, they never became popular for server application programming, with few exceptions like antivirus programs, backup programs and certain database products. Functionality Upon loading, a NLM requests resources, such as memory and process threads, from the NetWare kernel. The NetWare kernel tracks such requests, and can identify memory and other resources assigned to a specific NLM. NLMs may auto-load other NLMs upon which ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Executable And Linkable Format
In computing, the Executable and Linkable FormatTool Interface Standard (TIS) Portable Formats SpecificationVersion 1.1'' (October 1993) (ELF, formerly named Extensible Linking Format), is a common standard file format for executable files, object code, shared libraries, and core dumps. First published in the specification for the application binary interface (ABI) of the Unix operating system version named System V Release 4 (SVR4), and later in the Tool Interface Standard,Tool Interface Standard (TIS) Executable and Linking Format (ELF) SpecificationVersion 1.2'' (May 1995) it was quickly accepted among different vendors of Unix systems. In 1999, it was chosen as the standard binary file format for Unix and Unix-like systems on x86 processors by the 86open project. By design, the ELF format is flexible, extensible, and cross-platform. For instance, it supports different endiannesses and address sizes so it does not exclude any particular central processing unit (CPU) o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gold (linker)
In software engineering, gold is a linker for ELF files. It became an official GNU package and was added to binutils in March 2008 and first released in binutils version 2.19. gold was developed by Ian Lance Taylor and a small team at Google. The motivation for writing gold was to make a linker that is faster than the GNU linker, especially for large applications coded in C++. Unlike the GNU linker, gold does not use the BFD library to process object files. While this limits the object file formats it can process to ELF only, it is also claimed to result in a cleaner and faster implementation without an additional abstraction layer. The author cited complete removal of BFD as a reason to create a new linker from scratch rather than incrementally improve the GNU linker. This rewrite also fixes some bugs in old ld that break ELF files in various minor ways. To specify gold in a makefile, one sets the LD or LD environmental variable to ld.gold. To specify gold through a compiler o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dynamic-link Library
Dynamic-link library (DLL) is Microsoft's implementation of the shared library concept in the Microsoft Windows and OS/2 operating systems. These libraries usually have the file extension DLL, OCX (for libraries containing ActiveX controls), or DRV (for legacy system drivers). The file formats for DLLs are the same as for Windows EXE files – that is, Portable Executable (PE) for 32-bit and 64-bit Windows, and New Executable (NE) for 16-bit Windows. As with EXEs, DLLs can contain code, data, and resources, in any combination. Data files with the same file format as a DLL, but with different file extensions and possibly containing only resource sections, can be called ''resource DLLs''. Examples of such DLLs include ''icon libraries'', sometimes having the extension ICL, and font files, having the extensions FON and FOT. Background The first versions of Microsoft Windows ran programs together in a single address space. Every program was meant to co-operate by yield ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Name Mangling
In compiler construction, name mangling (also called name decoration) is a technique used to solve various problems caused by the need to resolve unique names for programming entities in many modern programming languages. It provides a way of encoding additional information in the name of a function, structure, class or another datatype in order to pass more semantic information from the compiler to the linker. The need for name mangling arises where the language allows different entities to be named with the same identifier as long as they occupy a different namespace (typically defined by a module, class, or explicit ''namespace'' directive) or have different signatures (such as in function overloading). It is required in these use cases because each signature might require different, specialized calling convention in the machine code. Any object code produced by compilers is usually linked with other pieces of object code (produced by the same or another compiler) by a type ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
