C Coding Standard

Overview .

The general requirements in this document and its appendices are intended to help the projects prepare C computer program source code that is readable, understandable, and easy to maintain. Any restrictions, rules, recommendations, and clarifications shall also be defined. All approved deviations/waivers from these standards shall be identified in the specific project Software Development Plan at the first occurrence explaining the reason why these software-coding standards are not being followed. Any subsets of the high order language (HOL) required for safety or security critical reasons shall be defined in the project specific safety or security programme plans.

ISO/IEC 12207/MIL-STD-498 specifies requirements necessary to develop and apply standards for representing software code. The project developer and subcontractors Software Development Plan (SDP) shall contain references to this C software coding standard when applicable. This software coding standard shall include standards for: format, header comments, naming conventions and any rules, recommendations, restrictions or clarifications on the use of the selected HOL programming language constructs or features, such as renaming, go to's, etc.

Safety or security critical software may require additional specific subset of the coding standards (e.g., a safe subset) to be developed that identify requirements for annotation of safety/security -critical code and limitation on use of certain language features that can reduce the risk of software to safety or security hazards/threats. The software safety activities shall be defined in the "System/Software Safety Process" document -- a technical overview of safety-critical strategy and coding practices for developers and safety engineers, primarily those involving restricting the use of certain programming language constructs. The software security-critical activities shall be defined in the "System/Software Security Management Process".

The document has been prepared using various referenced C coding standards in commercial use and have modified to suit the projects with the scope extended. This is still an evolving document and will be updated to reflect the latest standardization agreements. Please send comments and suggestions using the attached Document Change Request form

Any safety subset will be related to this document and shall be identified or defined in the project specific Software Development Plan (SDP) or Software Safety Programme Plan (SSPP).

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