Public API

The runtime library is not completely internal, also provides a public API. This API is mostly safe, and they may influence common runtime behavior or provide some additional opportunities.

Index

Variables
fn COMAXPROCS(): int
fn NumCPU(): int
async fn Yield()async fn Blocking()

Variables

const BigEndian: bool

Whether the running program's architecture is big-endian.

const LittleEndian: bool

Whether the running program's architecture is little-endian.

const OS: str

The running program's operating system target: one of darwin, linux and so on.
To view possible combinations of OS, run julec tool distos

const Arch: str

The running program's architecture target: one of i386, amd64 and so on.
To view possible combinations of OS, run julec tool distarch

const RCDelta: untyped integer

The reference counting data delta value that must occur per each reference counting operation.

COMAXPROCS

fn COMAXPROCS(): int

Returns the maximum number of CPUs that can be executing simultaneously.

NumCPU

fn NumCPU(): int

Returns the number of logical CPUs usable by the current process.

The set of available CPUs is checked by querying the operating system at process startup. Changes to operating system CPU allocation after process startup are not reflected.

Yield

async fn Yield()

Yields the processor, allowing other coroutines to run. It does not suspend the current coroutine, so execution resumes automatically.

Blocking

async fn Blocking(job: fn())

Executes the given job on the blocking thread-pool, isolating a potentially blocking operation from the scheduler.

The scheduler does NOT automatically detect or offload blocking operations. If a blocking call (e.g. file I/O or FFI) is executed directly, the underlying scheduler thread (M) will block.

Use this function when you want to explicitly prevent a blocking operation from stalling scheduler progress.

This function is opt-in and never used implicitly by the runtime.