Module task 

Structs

BlockingBridge

A capability, captured where the backend’s executor is reachable, to run async work from a plain blocking thread (iocsh, a REPL, a script thread).

Elapsed

The timeout’s error — “the deadline elapsed before the future completed”. Hosted this is tokio’s own type so timeout composes with tokio-aware callers; the exec backend substitutes a mirror (same Decision-B alias pattern as TaskJoinError — the consumed surface is Debug/Display only). Errors returned by Timeout.

Interval

Periodic ticker — the seam replacement for tokio::time::interval, so no production site names tokio::time directly (decision A2). The hosted build wraps tokio::time::Interval, preserving its default MissedTickBehavior::Burst catch-up and immediate first tick; the RTEMS build substitutes the runtime-free crate::runtime::background::timer_sleep::TimerInterval, which reproduces the same semantics over the delayed-callback timer.

MandatoryThread

A thread the IOC cannot correctly run without — the scan rates, the callback bands, the delayed-callback timer, the boot script.

RuntimeHandle

Handle to the runtime.

TaskSet

A set of spawned tasks, joined as they complete — the seam replacement for tokio::task::JoinSet.

Enums

NotBlockable

A synchronous caller asked to block on an async operation from a thread where blocking cannot be made sound.

PriorityApplied

Outcome of a best-effort OS-scheduler priority change.

RtPolicy

Whether this process may ask the OS for real-time scheduling.

StackSizeClass

Stack-size class — epicsThreadStackSizeClass (epicsThread.h:91).

ThreadPriority

EPICS thread priority — an integer 0..=99 with the named levels from epicsThreadPriority* (epicsThread.h:73-83). Lower values are lower priority; the CA server bands sit below the scan bands so scan threads preempt CA-server threads on a loaded IOC.

Constants

DEFAULT_POLICY

What RT_PRIORITY_ENV means when it is unset, for the target this was compiled for.

HAS_TOKIO_REACTOR

true when spawn lands the future on the tokio runtime, false when it lands on the reactor-free background executor (exec_backend — the RTEMS target, or a host build with --features rtems-exec-model).

PRIORITY_MAX

Maximum EPICS thread priority (epicsThreadPriorityMax).

PRIORITY_MIN

Minimum EPICS thread priority (epicsThreadPriorityMin).

RT_PRIORITY_ENV

Environment switch that opts this process in to real-time (SCHED_FIFO) scheduling for the IOC threads that carry an EPICS priority.

Functions

apply_to_current_thread

Apply an EPICS ThreadPriority to the current OS thread, best effort.

apply_to_current_thread_under

apply_to_current_thread with the real-time policy supplied by the caller instead of read from the environment.

block_on_sync

Block the calling thread on fut, picking the mechanism that is sound for the thread we are actually on.

enter_ioc_thread

The prologue an IOC thread runs as its first statement, when it takes on its role: publish its name to the OS, then request its scheduling band.

interval

Build a periodic ticker firing every period — the seam replacement for tokio::time::interval.

name_current_thread

Push std::thread::current().name() down to the OS thread object.

runtime_handle

sched_calls_made

How many times this process has asked the OS scheduler for SCHED_FIFO, across every thread — including the one-off range probe.

sleep

sleep_until

spawn

spawn_blocking

spawn_blocking_with_priority

Spawn a blocking closure on a dedicated thread and apply the given EPICS ThreadPriority to that thread before running f.

spawn_dedicated_thread

Spawn a dedicated OS thread that runs f at priority with a stack of StackSizeClass, plus whatever ambient async context block_on_sync needs on this target.

test_block_on

Drive an async test body to completion — the driver behind #[epics_test] (epics-macros-rs).

timeout

Await fut, giving up after duration — the seam’s only bounded wait.

timeout_at

timeout against an absolute Instant instead of a duration — the seam’s tokio::time::timeout_at.

yield_now

Yield the current task once — the seam replacement for tokio::task::yield_now, so no call site names tokio::task directly.

Type Aliases

Instant

The instant sleep_until measures deadlines against — the backend’s own clock, which is the whole point of naming it here.

TaskAbortHandle

Detached cancellation handle for a spawned task.

TaskHandle

Handle to a spawned task — await for its result, abort() to cancel.

TaskJoinError

Error from awaiting a TaskHandle (cancelled or panicked).