pub const PIO_ABI_VERSION: u32 = 4;Expand description
ABI version of this C interface. Bump on any breaking change to an existing
pio_* signature or to the powerio-json snapshot schema (new additive
symbols don’t require a bump). A consumer compares pio_abi_version
against the value it was built against (the PIO_ABI_VERSION macro in
powerio.h) and refuses a mismatched library instead of calling in blind.
v4 froze the naming grammar and conventions (see the header preamble); the
surface evolves additively from here: new data means new symbols, and rich
or multiconductor data rides the Arrow and powerio-json schemas, which
carry their own structure and never force a signature change.