ngx.headers_sent ---------------- **语法:** *value = ngx.headers_sent* **环境:** *set_by_lua*, rewrite_by_lua*, access_by_lua*, content_by_lua** 如果应答头部已经被发送（通过 ngx_lua）返回 `true` ，否则返回 `false` 。 该 API 是在 `v0.3.1rc6` 版本首次引入的。 [返回目录](#nginx-api-for-lua) > English source: ngx.headers_sent ---------------- **syntax:** *value = ngx.headers_sent* **context:** *set_by_lua*, rewrite_by_lua*, access_by_lua*, content_by_lua** Returns `true` if the response headers have been sent (by ngx_lua), and `false` otherwise. This API was first introduced in ngx_lua v0.3.1rc6. [Back to TOC](#nginx-api-for-lua)