2016-03-25 23:28:31 +00:00
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Use in C {#flatbuffers_guide_use_c}
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==========
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The C language binding exists in a separate project named [FlatCC](https://github.com/dvidelabs/flatcc).
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The `flatcc` C schema compiler can generate code offline as well as
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online via a C library. It can also generate buffer verifiers and fast
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JSON parsers, printers.
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Great effort has been made to ensure compatibily with the main `flatc`
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project.
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## General Documention
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- [Tutorial](@ref flatbuffers_guide_tutorial) - select C as language
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when scrolling down
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2016-03-26 08:22:56 +00:00
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- General Use in C (README) <https://github.com/dvidelabs/flatcc/blob/master/README.md>
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- The C Builder Interface (advanced) <https://github.com/dvidelabs/flatcc/blob/master/doc/builder.md>
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2016-03-25 23:28:31 +00:00
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## Basic Reflection
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The C-API does support reading binary schema (.bfbs)
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files via code generated from the `reflection.fbs` schema, and an
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[example usage](https://github.com/dvidelabs/flatcc/tree/master/samples/reflection)
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shows how to use this. The schema files are pre-generated
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2016-03-26 08:22:56 +00:00
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in the [runtime distribution](https://github.com/dvidelabs/flatcc/tree/master/include/flatcc/reflection).
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2016-03-25 23:28:31 +00:00
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## Mutating Reflection
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The C-API does not support mutating reflection like C++ does.
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Although the following isn't reflection, it is possible to create new
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buffers using complex objects from existing buffers as source. This can
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be very efficient due to direct copy semantics without endian conversion or
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temporary stack allocation.
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2016-03-26 08:22:56 +00:00
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Scalars, structs and strings can be used as source, as well vectors of
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these.
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2016-03-25 23:28:31 +00:00
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It is currently not possible to use an existing table or vector of table
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as source, but it would be possible to add support for this at some
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2016-03-26 08:22:56 +00:00
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point. Vectors of strings
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2016-03-25 23:28:31 +00:00
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## Why not integrate with the `flatc` tool?
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[It was considered how the C code generator could be integrated into the
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`flatc` tool](https://github.com/dvidelabs/flatcc/issues/1), but it
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would either require that the standalone C implementation of the schema
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compiler was dropped, or it would lead to excessive code duplication, or
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a complicated intermediate representation would have to be invented.
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Neither of these alternatives are very attractive, and it isn't a big
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deal to use the `flatcc` tool instead of `flatc` given that the
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FlatBuffers C runtime library needs to be made available regardless.
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