Concurrency Reference

kostroutine

  • kostroutine fn(args...) schedules a function on runtime worker threads.

  • waitAll() blocks until all scheduled routines finish.

  • time.after(ms) returns a channel that receives once after timeout.

Channels

Create channels:

  • chan() for unbounded channels

  • chan(n) for buffered channels (n must be > 0)

Channel operations:

  • send(ch, value)

  • recv(ch)

  • close(ch)

  • trySend(ch, value) returns bool

  • tryRecv(ch, fallback) returns received value or fallback

select

Supported case forms:

  • case recv(ch) as v:

  • case send(ch, v):

  • case timeout(ms):

  • default:

Current behavior:

  • deterministic selection (first ready case in source order)

  • timeout(ms) requires non-negative int milliseconds

Common pattern

Use timeout channel from time.after:

import (
    "time"
)

done = time.after(500)
select:
    case recv(done):
        print("timeout reached")