Meziantou.Framework

Cancellation and killing

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Cancel with a token

using var cts = new CancellationTokenSource(TimeSpan.FromSeconds(5));
await ProcessWrapper.Create("long-running-process")
    .ExecuteAsync(cts.Token);  // throws OperationCanceledException if cancelled

When the token is canceled, the process and all its descendants are killed, and awaiting the instance throws an OperationCanceledException. The validation does not run for a canceled process. When the token is already canceled, ExecuteAsync throws without starting the process.

Kill a process

ExecuteAsync returns as soon as the process is started, so you can kill it while it runs:

var process = ProcessWrapper.Create("long-running-process")
    .WithValidation(ProcessValidationMode.None)
    .ExecuteAsync();

process.Kill(); // or process.Kill(entireProcessTree: false)
await process;
  • Kill() kills the process and its descendants. Kill(entireProcessTree: false) kills only the process.
  • Killing a process that already exited does nothing.
  • A killed process usually exits with a non-zero exit code: disable the validation, as in the example, or catch the ProcessExecutionException.

Send a signal

On .NET 11, ProcessInstance.Signal(PosixSignal) sends a signal to the process, such as SIGTERM to ask it to stop gracefully. It returns the result of the operating system call, and throws an InvalidOperationException once the process has exited and its handle was released.

The process handle

ProcessInstance.ProcessId and StartDate identify the running process. UnsafeGetProcessHandle returns its SafeProcessHandle, for native APIs, or null once the process has exited: the handle is released as soon as the process exits, even if you never await the instance.