Don't break your users: keep your API/ABI stable!
summary
Symbol versioning attaches version nodes to exported symbols so old binaries keep finding the same symbol names at runtime; map files define those version nodes and are passed to the linker with --version-script. Creating aliases with assembler directives and marking implementations with a single @ mark or double @@ mark lets two versions coexist. The tool abimap updates map files (commands: new, update, check, version, final), checks for accidental removals, requires the full exported-symbol list, and cannot auto-extract symbols or move an existing symbol into a new version.
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chapters (7)
- 0:00Intro
- 0:26Agenda
- 2:59Versioning
- 4:48Map files
- 10:35Making incompatible changes
- 13:08Updating the map files
- 18:04Summary
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