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Memory Dump
In computing, a core dump, memory dump, crash dump, storage dump, system dump, or ABEND dump consists of the recorded state of the working memory of a computer program at a specific time, generally when the program has crashed or otherwise terminated abnormally. In practice, other key pieces of program state are usually dumped at the same time, including the processor registers, which may include the program counter and stack pointer, memory management information, and other processor and operating system flags and information. A snapshot dump (or snap dump) is a memory dump requested by the computer operator or by the running program, after which the program is able to continue. Core dumps are often used to assist in diagnosing and debugging errors in computer programs. On many operating systems, a fatal exception in a program automatically triggers a core dump. By extension, the phrase "to dump core" has come to mean in many cases, any fatal error, regardless of whether a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Magnetic Core
A magnetic core is a piece of magnetism, magnetic material with a high magnetic permeability used to confine and guide magnetic fields in electrical, electromechanical and magnetic devices such as electromagnets, transformers, electric motors, electric generator, generators, inductors, loudspeakers, magnetic recording heads, and magnetic assemblies. It is made of ferromagnetic metal such as iron, or ferrimagnetic compounds such as Ferrite (magnet), ferrites. The high permeability, relative to the surrounding air, causes the magnetic field lines to be concentrated in the core material. The magnetic field is often created by a current-carrying coil of wire around the core. The use of a magnetic core can increase the strength of magnetic field in an electromagnetic coil by a factor of several hundred times what it would be without the core. However, magnetic cores have side effects which must be taken into account. In alternating current (AC) devices they cause energy losses, call ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Octal
Octal (base 8) is a numeral system with eight as the base. In the decimal system, each place is a power of ten. For example: : \mathbf_ = \mathbf \times 10^1 + \mathbf \times 10^0 In the octal system, each place is a power of eight. For example: : \mathbf_8 = \mathbf \times 8^2 + \mathbf \times 8^1 + \mathbf \times 8^0 By performing the calculation above in the familiar decimal system, we see why 112 in octal is equal to 64+8+2=74 in decimal. Octal numerals can be easily converted from binary representations (similar to a quaternary numeral system) by grouping consecutive binary digits into groups of three (starting from the right, for integers). For example, the binary representation for decimal 74 is 1001010. Two zeroes can be added at the left: , corresponding to the octal digits , yielding the octal representation 112. Usage In China The eight bagua or trigrams of the I Ching correspond to octal digits: * 0 = ☷, 1 = ☳, 2 = ☵, 3 = ☱, * 4 = ☶, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
WinDbg
WinDbg is a multipurpose debugger for the Microsoft Windows computer operating system, distributed by Microsoft. It can be used to debug user mode applications, device drivers, and the operating system itself in kernel mode. Overview Like the Visual Studio Debugger, WinDbg has a graphical user interface (GUI), but is more powerful and has little else in common. WinDbg can automatically load debugging symbol files (e.g., PDB files) from a server by using a unique ID embedded in the executable (using the "RSDS Guid") via SymSrv (SymSrv.dll), instead of requiring users to manually find the files. If a private symbol server is configured, the symbols can be correlated with the source code for the binary. This eases the burden of debugging problems that have various versions of binaries installed on the debugging target by eliminating the need for finding and installing specific symbols version on the debug host. Microsoft has a public symbol server that has most of the public sym ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Z/VM
z/VM is the current version in IBM's VM family of virtual machine operating systems. First released in October 2000, z/VM remains in active use and development . It is directly based on technology and concepts dating back to the 1960s, particularly IBM's CP/CMS on the IBM System/360-67 (see article History of CP/CMS for historical details). z/VM runs on IBM's IBM Z family of computers and can support large numbers (thousands) of Linux virtual machines. (See Linux on IBM Z.) On 16 September 2022, IBM released z/VM Version 7.3 which requires z/Architecture, implemented in IBM's EC12, BC12 and later models. See also * OpenSolaris for System z * PR/SM * Time-sharing system evolution * z/OS * z/TPF * z/VSE References Citations ; Primary CP/CMS sources: * R. J. Creasy,The origin of the VM/370 time-sharing system, ''IBM Journal of Research & Development'', Vol. 25, No. 5 (September 1981), ''pp.'' 483–90, PDF― perspective on CP/CMS and VM history by the CP-40 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Z/OS
z/OS is a 64-bit operating system for IBM z/Architecture mainframes, introduced by IBM in October 2000. It derives from and is the successor to OS/390, which in turn was preceded by a string of MVS versions.Starting with the earliest: * OS/VS2 Release 2 through Release 3.8 * MVS/System Extensions (MVS/SE) * MVS/System Product (MVS/SP) Version 1 * MVS/System Product Version 2 (MVS/Extended Architecture, MVS/XA) * MVS/System Product Version 3 (MVS/Enterprise Systems Architecture, MVS/ESA) * MVS/ESA SP Version 4 * MVS/ESA SP Version 5 Like OS/390, z/OS combines a number of formerly separate, related products, some of which are still optional. z/OS has the attributes of modern operating systems but also retains much of the older functionality that originated in the 1960s and is still in regular use—z/OS is designed for backward compatibility. Major characteristics z/OS supportsSome, e.g., TSO/E, are bundled with z/OS, others, e.g., CICS, are separately priced. stable ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Linux
Linux ( ) is a family of open source Unix-like operating systems based on the Linux kernel, an kernel (operating system), operating system kernel first released on September 17, 1991, by Linus Torvalds. Linux is typically package manager, packaged as a Linux distribution (distro), which includes the kernel and supporting system software and library (computing), libraries—most of which are provided by third parties—to create a complete operating system, designed as a clone of Unix and released under the copyleft GPL license. List of Linux distributions, Thousands of Linux distributions exist, many based directly or indirectly on other distributions; popular Linux distributions include Debian, Fedora Linux, Linux Mint, Arch Linux, and Ubuntu, while commercial distributions include Red Hat Enterprise Linux, SUSE Linux Enterprise, and ChromeOS. Linux distributions are frequently used in server platforms. Many Linux distributions use the word "Linux" in their name, but the Free ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kdump (Linux)
kdump is a feature of the Linux kernel that creates crash dumps in the event of a kernel crash. When triggered, kdump exports a memory image (also known as vmcore) that can be analyzed for the purposes of debugging and determining the cause of a crash. The dumped image of main memory, exported as an Executable and Linkable Format (ELF) object, can be accessed either directly through during the handling of a kernel crash, or it can be automatically saved to a locally accessible file system, to a raw device, or to a remote system accessible over Computer network, network. Internals In the event of a kernel crash, kdump preserves system consistency by booting another Linux kernel, which is known as the ''dump-capture kernel'', and using it to export and save a memory dump. As a result, the system boots into a clean and reliable environment instead of relying on an already crashed kernel that may cause various issues, such as causing file system Data corruption, corruption while w ... [...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. 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. otool and nm perform analogous functions for Mach-O files. Example For example, $ objdump -D -M intel file.bin This disassembles the file file.bin, showing its assembly code in Intel syntax. Example output: 4004ed : 4004ed: 55 push rbp 4004ee: 48 89 e5 mov rbp,rsp 4004f1: c7 45 ec 00 00 00 00 mov DWORD PTR bp-0x140x0 4004f8: c7 45 f0 01 00 00 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Unix-like
A Unix-like (sometimes referred to as UN*X, *nix or *NIX) operating system is one that behaves in a manner similar to a Unix system, although not necessarily conforming to or being certified to any version of the Single UNIX Specification. A Unix-like Application software, application is one that behaves like the corresponding List of POSIX commands, Unix command or Unix shell, shell. Although there are general Unix philosophy, philosophies for Unix design, there is no technical standard defining the term, and opinions can differ about the degree to which a particular operating system or application is Unix-like. Some well-known examples of Unix-like operating systems include Linux, FreeBSD and OpenBSD. These systems are often used on servers as well as on personal computers and other devices. Many popular applications, such as the Apache HTTP Server, Apache web server and the Bash (Unix shell), Bash shell, are also designed to be used on Unix-like systems. Definition The Open ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Unix
Unix (, ; trademarked as UNIX) is a family of multitasking, multi-user computer operating systems that derive from the original AT&T Unix, whose development started in 1969 at the Bell Labs research center by Ken Thompson, Dennis Ritchie, and others. Initially intended for use inside the Bell System, AT&T licensed Unix to outside parties in the late 1970s, leading to a variety of both academic and commercial Unix variants from vendors including University of California, Berkeley ( BSD), Microsoft (Xenix), Sun Microsystems ( SunOS/ Solaris), HP/ HPE ( HP-UX), and IBM ( AIX). The early versions of Unix—which are retrospectively referred to as " Research Unix"—ran on computers such as the PDP-11 and VAX; Unix was commonly used on minicomputers and mainframes from the 1970s onwards. It distinguished itself from its predecessors as the first portable operating system: almost the entire operating system is written in the C programming language (in 1973), which allows U ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Address Space
In computing, an address space defines a range of discrete addresses, each of which may correspond to a network host, peripheral device, disk sector, a memory cell or other logical or physical entity. For software programs to save and retrieve stored data, each datum must have an address where it can be located. The number of address spaces available depends on the underlying address structure, which is usually limited by the computer architecture being used. Often an address space in a system with virtual memory corresponds to a highest level translation table, e.g., a segment table in IBM System/370. Address spaces are created by combining enough uniquely identified qualifiers to make an address unambiguous within the address space. For a person's physical address, the ''address space'' would be a combination of locations, such as a neighborhood, town, city, or country. Some elements of a data address space may be the same, but if any element in the address is different, ad ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Disassembler
A disassembler is a computer program that translates machine language into assembly language—the inverse operation to that of an assembler. The output of disassembly is typically formatted for human-readability rather than for input to an assembler, making disassemblers primarily a reverse-engineering tool. Common uses include analyzing the output of high-level programming language compilers and their optimizations, recovering source code when the original is lost, performing malware analysis, modifying software (such as binary patching), and software cracking. A disassembler differs from a decompiler, which targets a high-level language rather than an assembly language. Assembly language source code generally permits the use of constants and programmer comments. These are usually removed from the assembled machine code by the assembler. If so, a disassembler operating on the machine code would produce disassembly lacking these constants and comments; the disassembled outpu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
