% 1 - ορισμός. Τι είναι το byte-codes
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Τι (ποιος) είναι byte-codes - ορισμός

FORM OF INSTRUCTION SET DESIGNED TO BE RUN BY A SOFTWARE INTERPRETER
Byte code; P-Code; P-Codes; Intermediate code; Byte-code; Bitcode; Byte Code; Bytecodes; Portable code; P-code; Byte-compile; Byte-compiler; Byte-code compiler

byte-code         
<file format, software> A binary file containing an executable program, consisting of a sequence of (op code, data) pairs. Byte-code op codes are most often fixed size binary patterns, but can be variable size. The data portion consists of zero or more bits whose format typically depends on the op code. A byte-code program is interpreted by a {byte-code interpreter}. The advantage of this technique compared with outputing machine code for some particular processor is that the same byte-code can be executed on any processor on which the byte-code interpreter runs. The byte-code may be compiled to machine code ("native code") for speed of execution but this usually requires significantly greater effort for each new taraget architecture than simply porting the interpreter. For example, Java is compiled to byte-code which runs on the Java Virtual Machine. (2006-05-29)
byte         
  • ''Byte'' leased an office for one of their West Coast Branch operations in this building in [[Costa Mesa, California]] (pictured in 2022)
AMERICAN COMPUTING MAGAZINE
BYTE Magazine; BYTE magazine; Byte magazine; BiX -- The Byte Information Exchange; BYTE; Byte Magazine; Byte Publications Inc.; BYTE (magazine); BYTE Publications Inc.; BYTE Publications, Inc.; BYTE Publications; Byte Publications, Inc.; Byte Publications; BYTE - The small systems journal; BYTE Books; Byte - the Small Systems Journal; Byte: The Small Systems Journal; BYTE - the small systems journal; BYTE - the Small Systems Journal
<unit> /bi:t/ (B) A component in the machine data hierarchy larger than a bit and usually smaller than a word; now nearly always eight bits and the smallest addressable unit of storage. A byte typically holds one character. A byte may be 9 bits on 36-bit computers. Some older architectures used "byte" for quantities of 6 or 7 bits, and the PDP-10 and IBM 7030 supported "bytes" that were actually bit-fields of 1 to 36 (or 64) bits! These usages are now obsolete, and even 9-bit bytes have become rare in the general trend toward power-of-2 word sizes. The term was coined by Werner Buchholz in 1956 during the early design phase for the IBM Stretch computer. It was a mutation of the word "bite" intended to avoid confusion with "bit". In 1962 he described it as "a group of bits used to encode a character, or the number of bits transmitted in parallel to and from input-output units". The move to an 8-bit byte happened in late 1956, and this size was later adopted and promulgated as a standard by the System/360 operating system (announced April 1964). James S. Jones <jsjones@graceland.edu> adds: I am sure I read in a mid-1970's brochure by IBM that outlined the history of computers that BYTE was an acronym that stood for "Bit asYnchronous Transmission E..?" which related to width of the bus between the Stretch CPU and its CRT-memory (prior to Core). Terry Carr <bear@mich.com> says: In the early days IBM taught that a series of bits transferred together (like so many yoked oxen) formed a Binary Yoked Transfer Element (BYTE). [True origin? First 8-bit byte architecture?] See also nibble, octet. [Jargon File] (2003-09-21)
byte         
  • ''Byte'' leased an office for one of their West Coast Branch operations in this building in [[Costa Mesa, California]] (pictured in 2022)
AMERICAN COMPUTING MAGAZINE
BYTE Magazine; BYTE magazine; Byte magazine; BiX -- The Byte Information Exchange; BYTE; Byte Magazine; Byte Publications Inc.; BYTE (magazine); BYTE Publications Inc.; BYTE Publications, Inc.; BYTE Publications; Byte Publications, Inc.; Byte Publications; BYTE - The small systems journal; BYTE Books; Byte - the Small Systems Journal; Byte: The Small Systems Journal; BYTE - the small systems journal; BYTE - the Small Systems Journal
[b??t]
¦ noun Computing a group of binary digits or bits (usually eight) operated on as a unit.
?such a group as a unit of memory size.
Origin
1960s: an arbitrary formation based on bit4 and bite.

Βικιπαίδεια

Bytecode

Bytecode (also called portable code or p-code) is a form of instruction set designed for efficient execution by a software interpreter. Unlike human-readable source code, bytecodes are compact numeric codes, constants, and references (normally numeric addresses) that encode the result of compiler parsing and performing semantic analysis of things like type, scope, and nesting depths of program objects.

The name bytecode stems from instruction sets that have one-byte opcodes followed by optional parameters. Intermediate representations such as bytecode may be output by programming language implementations to ease interpretation, or it may be used to reduce hardware and operating system dependence by allowing the same code to run cross-platform, on different devices. Bytecode may often be either directly executed on a virtual machine (a p-code machine, i.e., interpreter), or it may be further compiled into machine code for better performance.

Since bytecode instructions are processed by software, they may be arbitrarily complex, but are nonetheless often akin to traditional hardware instructions: virtual stack machines are the most common, but virtual register machines have been built also. Different parts may often be stored in separate files, similar to object modules, but dynamically loaded during execution.