return serve(hook).then(null, err => {
			if (!retry || platform.isWindows || err.code !== 'EADDRINUSE') {
				return TPromise.wrapError(err);
			}

			// should retry, not windows and eaddrinuse

			return connect(hook).then(
				client => {
					// we could connect to a running instance. this is not good, abort
					client.dispose();
					return TPromise.wrapError(new Error('There is an instance already running.'));
				},
				err => {
					// it happens on Linux and OS X that the pipe is left behind
					// let's delete it, since we can't connect to it
					// and the retry the whole thing
					try {
						fs.unlinkSync(hook);
					} catch (e) {
						return TPromise.wrapError(new Error('Error deleting the shared ipc hook.'));
					}

					return setup(false);
				}
			);
		});

function main(argv: string[]): void {
	if (argv.length !== 5) {
		return fatal('Wrong number of arguments');
	}

	if (!process.env['VSCODE_IPC_HOOK']) {
		return fatal('Missing ipc hook');
	}

	if (!process.env['VSCODE_GIT_REQUEST_ID']) {
		return fatal('Missing git id');
	}

	var id = process.env['VSCODE_GIT_REQUEST_ID'];
	var request = argv[2];
	var host = argv[4].substring(1, argv[4].length - 2);

	connect(process.env['VSCODE_IPC_HOOK'])
		.then(client => {
			const service = client.getService<GitAskpassServiceStub>('GitAskpassService', GitAskpassServiceStub);

			return service.askpass(id, host, process.env['MONACO_GIT_COMMAND']).then(result => {
				if (result) {
					console.log(/^Username$/i.test(request) ? result.username : result.password);
				}

				return client;
			});
		})
		.done(c => {
			c.dispose();
			setTimeout(() => process.exit(0), 0);
		});
}

		return serve(env.mainIPCHandle).then(null, err => {
			if (err.code !== 'EADDRINUSE') {
				return Promise.wrapError(err);
			}

			// there's a running instance, let's connect to it
			return connect(env.mainIPCHandle).then(
				client => {
					env.log('Sending env to running instance...');

					const service = client.getService<LaunchService>('LaunchService', LaunchService);

					return service.start(env.cliArgs)
						.then(() => client.dispose())
						.then(() => Promise.wrapError('Sent env to running instance. Terminating...'));
				},
				err => {
					if (!retry || platform.isWindows || err.code !== 'ECONNREFUSED') {
						return Promise.wrapError(err);
					}

					// it happens on Linux and OS X that the pipe is left behind
					// let's delete it, since we can't connect to it
					// and the retry the whole thing
					try {
						fs.unlinkSync(env.mainIPCHandle);
					} catch (e) {
						env.log('Fatal error deleting obsolete instance handle', e);
						return Promise.wrapError(e);
					}

					return setup(false);
				}
			);
		});

function connectToSharedProcess(): TPromise<Client> {
	return connect(process.env['VSCODE_SHARED_IPC_HOOK']);
}