v0.21

• Add Bazel build rules.

v0.20

• Update URLs to point to the new CloudABI web site.
• Add proper extern "C" tags for C++.

v0.19

• Add a reserved errno code for success. This is needed for languages that have closed enums.
• Allow locks and condvar sleeps to be used in combination with relative timeouts. This is useful for implementing threading APIs that use relative timeouts.
• Add Rust bindings.
• No longer create inline wrappers for system calls to improve ABI stability.

v0.18

• Make style of the ARMv6 vDSO more consistent.
• Add a vDSO for running ARMv6 binaries on 64-bit architectures (AArch64).

v0.17

• Add CLOUDABI_AT_PID to uniquely identify the running process. This field does not contain a numerical pid, but a UUIDv4 to provide unique identification in distributed contexts.
• Remove fields that have become unnecessary due to simplifications to the polling framework.