concurrency

# Concurrency This is a library providing support for concurrently running subprocesses. Subprocesses do not share memory with the parent process. Communication is realised by means of message passing.

# Changelog ## 4.0.0 - Feature: add `exitCodeIn` returning the exit code of a terminated process given an `ExitStatus`. - Feature: add `signalIn` returning the number of the signal that caused the process to terminate, if applicable. - Feature: add `hadCoreDump` returning if the terminated process produced a coredump. - Change: `terminate` now returns an `ExitStatus` instead of an `Int`. - Change: `terminateBySubProcessId` now returns an `ExitStatus` instead of an `Int`. - Change: `waitForSubProcessToTerminate` now returns an `ExitStatus` instead of an `Int`. - Change: `waitForNextSubProcessToTerminate` now returns an `ExitStatus` instead of an `Int`. - Change: `waitForSubProcessToTerminateById` now returns an `ExitStatus` instead of an `Int`. - Change: `checkIfSubProcessTerminated` now returns an `ExitStatus` instead of an `Int`. - Change: `checkIfAnySubProcessTerminated` now returns an `ExitStatus` instead of an `Int`. - Change: `checkIfSubProcessTerminatedById` now returns an `ExitStatus` instead of an `Int`. #### 3.3.2 - Fix: include `SubProcessInterface.o` in package. #### 3.3.1 - Enhancement: optimise `receive` for large messages. ### 3.3.0 - Feature: add `checkIfSubProcessTerminated`, `checkIfSubProcessTerminatedById` and `checkIfAnySubProcessTerminated`. - Feature: add `==` and `<` instance for `SubProcessId`. ### 3.2.0 - Feature: add `waitForNextSubProcessToTerminate`. #### 3.1.1 - Chore: support base `3.0`. ### 3.1.0 - Feature: Add json derivations for `:: SubProcessId`. #### 3.0.2 - Fix: occasional garbage messages provided by `receive` in case sub-processes terminate. #### 3.0.1 - Chore: support containers ^2. ## 3.0.0 - Change: support base 2.0 and require an instance for the `SysCallEnv` class for environments involved in functions which perform syscalls. #### 2.2.1 - Chore: update graph-copy dependency. ### 2.2.0 - Feature: Add `createChannel`, `closeInChannel` and `closeOutChannel`, enabling more customised usage of channels for communication between subprocesses. - Feature: Add `setBufferSize` and leave buffer size on default when creating channels, enabling more control of buffer sizes to tune performance. ### 2.1.0 - Chore: Add `toString` instance for `:: SubProcessId`. ## 2.0.0 - Feature: provide sub-processes' exit code when terminating/waiting for termination. #### 1.3.1 - Fix: fix mode of lockfiles created by `LockFile.withLockFile`. ### 1.3.0 - Enhancement: document `receive` output channel closed error and add `OUTPUT_CHANNEL_CLOSED` constant. ### 1.2.0 - Feature: add a `LockFile` module for synchronising the work of concurrent processes. ### 1.1.0 - Feature: add a `peek` function for messages. - Enhancement: allow to use messages of unique types. - Fix: do not close pipes before waiting for a process to terminate. - Fix: terminate process before closing pipes, to allow processes to gracefully handle term signals. - Fix: `receive` yields an error when there is no data on the pipe (e.g. when it is closed); prevents a busy infinite loop. ## 1.0.0 - Initial version