new post: pthread_cancel in c++

1 files changed, 40 insertions, 0 deletions

diff --git a/content/20210515-pthread_cancel-noexcept/thread.cc b/content/20210515-pthread_cancel-noexcept/thread.cc
new file mode 100644
index 0000000..73370be
--- /dev/null
+++ b/content/20210515-pthread_cancel-noexcept/thread.cc
@@ -0,0 +1,40 @@
+// file   : thread.cc
+// compile: g++ thread.cc -o thread -lpthread
+
+#include <atomic>
+
+#include <pthread.h>
+#include <unistd.h>
+
+struct S {
+    ~S() {
+        const char msg[] = "cancellation-point\n";
+        // write() -> pthread cancellation point.
+        write(STDOUT_FILENO, msg, sizeof(msg));
+    }
+};
+
+std::atomic<bool> gReleaseThread{false};
+
+void* threadFn(void*) {
+    while (!gReleaseThread) {}
+
+    // Hit cancellation point in destructor which
+    // is implicitly `noexcept`.
+    S s;
+
+    return nullptr;
+}
+
+int main() {
+    pthread_t t;
+    pthread_create(&t, nullptr /* attr */, threadFn, nullptr /* arg */);
+
+    // Cancel thread and release it to hit the cancellation point.
+    pthread_cancel(t);
+    gReleaseThread = true;
+
+    pthread_join(t, nullptr /* retval */);
+
+    return 0;
+}