The Youxian guchui 幽閒鼓吹 "Drums and Pipes from Amidst the Dark" is a collection of stories written by the Tang period 唐 (618-907) scholar Zhang Gu 張固, about whom practically nothing is known. The postface, written by the Ming period 明 (1368-1644) scholar Gu Yuanqing 顧元慶 says that he lived during the reigns of the emperors Yizong 唐懿宗 (r. 859-873) and Xizong 唐僖宗 (r. 873-888), and that he collected stories from the time of Emperor Xuanzong 唐宣宗 (r. 846-859). The short book includes 25 chapters that are written in a very refined way, and can so serve as additional sources to the history of the late Tang period. In the bibliographic chapters of the official dynastic histories Xintangshu 新唐志 and Songshi 宋史, the encyclopedia Wenxian tongkao 文獻通考 and in the bibliographies Chongwen zongmu 崇文總目, Junzhai dushu zhi 郡齋讀書志 and Zhizhai shulu jieti 直齋書錄解題, it is nevertheless categorized as a novella (xiaoshuo 小說).
The Youxian guchui is to be found in the collectanea Xu baichuan xuehai 續百川學海, Gushi wenfang xiaoshuo 顧氏文房小說, Lidai xiaoshi 歷代小史, Baoyantang miji 寶顏堂秘笈, Shuofu 說郛, Tangren shuohui 唐人說薈, Tangdai congshu 唐代叢書, Xuehai leibian 學海類編 and Shuoku 說庫. In 1958 the Zhonghua shuju press 中華書局 published a modern print in a joint edition with the books Da-Tang zhuanzai 大唐傳載 and Zhongchao gushi 中朝故事.
Source: Li Xueqin 李學勤, Lü Wenyu 呂文鬰 (1996). Siku da cidian 四庫大辭典, Changchun: Jilin daxue chubanshe, vol. 2, p. 2140.