ISO/IEC 9899:2024

This document specifies the form and establishes the interpretation of programs written in the C programming language. It is designed to promote the portability of C programs among a variety of data-processing systems. It is intended for use by implementers and programmers. It specifies: — the representation of C programs; — the syntax and constraints of the C language; — the semantic rules for interpreting C programs; — the representation of input data to be processed by C programs; — the representation of output data produced by C programs; — the restrictions and limits imposed by a conforming implementation of C. This document does not specify: — the mechanism by which C programs are transformed for use by a data-processing system; — the mechanism by which C programs are invoked for use by a data-processing system; — the mechanism by which input data are transformed for use by a C program; — the mechanism by which output data are transformed after being produced by a C program; — the size or complexity of a program and its data that will exceed the capacity of any specific data-processing system or the capacity of a particular processor; — all minimal requirements of a data-processing system that is capable of supporting a conforming implementation. Annex J gives an overview of portability issues that a C program can encounter.