public let process: Process

private let fileHandlePairs: [FileHandlePair]

private var terminationStatus: Int?

// Note: Even thoguh we do not use `fileHandlePairs`, we must retain them here until the process terminates otherwise their handlers will not be called.

init(process: Process, fileHandlePairs: [FileHandlePair] = []) {

self.process = process

self.fileHandlePairs = fileHandlePairs

}

public var isRunning: Bool {

self.process.isRunning

}

public var didFinishRunning: Bool {

!self.process.isRunning

}

public var exitStatus: Int? {

guard self.didFinishRunning else { return nil }

return Int(self.process.terminationStatus)

}

public func exitStatus() async -> Int {

if let terminationStatus = terminationStatus {

return terminationStatus

}

return await withCheckedContinuation { continuation in

let exitStatus = self.wait()

continuation.resume(returning: exitStatus)

}

}

public func wait() -> Int {

if let terminationStatus = terminationStatus {

return terminationStatus

}

self.process.waitUntilExit()

let terminationStatus = Int(self.process.terminationStatus)

self.terminationStatus = terminationStatus

return terminationStatus

}