condition handler的意思|示意

Note that condition functions are not asynchronously signal-safe and should not be called from a signal handler.

注意，条件函数并不是异步信号安全的，因此不能在信号处理函数中调用。

If a user is not authenticated when trying to access this resource, the user will receive a 401 status code and the application can provide a special error handler to deal with that condition.

如果用户在尝试访问这个资源时还没有经过身份验证，那么用户会收到401状态码，应用程序可以提供一个特殊的错误处理函数来处理这种情况。

In the case of the DB2 example in the left column of Table 3, if a particular SQL statement fails and generates an error, control is passed to the condition handler.

对于表3左侧列的DB 2示例，如果某条sql语句失败并生成一个错误，那么控制将被传递给条件处理程序。