--- /dev/null
+/*
+ * Copyright © 2013 Canonical Ltd.
+ *
+ * This program is free software: you can redistribute it and/or modify it
+ * under the terms of the GNU Lesser General Public License version 3,
+ * as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ *
+ * Authored by: Thomas Voß <thomas.voss@canonical.com>
+ */
+
+#include <core/posix/process_group.h>
+
+namespace core
+{
+namespace posix
+{
+struct ProcessGroup::Private
+{
+ pid_t id;
+};
+
+pid_t ProcessGroup::id() const
+{
+ return d->id;
+}
+
+ProcessGroup::ProcessGroup(pid_t id)
+ : Signalable(-id), // We rely on ::kill to deliver signals, thus negate the id (see man 2 kill).
+ d(new Private{id})
+{
+}
+
+ProcessGroup ProcessGroup::invalid()
+{
+ static const pid_t invalid_pid = 1;
+ return ProcessGroup(invalid_pid);
+}
+}
+}