byte-code

file format, software A binary file containing an

executable program, formed by 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, the format of the data portion may be

determined by the identifier. The data is most often variable

in size.

In some cases, by clever design, (e.g. some RISC

instruction sets) the identifier/data pair is a fixed size.

This can provide performance benefits.

A byte-code program is normally interpreted by a byte-codeinterpreter. The advantage of this technique compared with

outputing machine code for a 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.

(1998-08-30)