1. 2019-12-06
umount disk: 弹出u盘的时候解决u盘被哪个程序占用问题
i) lsof
lsof (list open files)
lsof | grep ****
ii) pgrep pkill -- look up or signal processes based on name and other attributes
pgrep *** --look through the currently running processes and lists the process IDs which match the selection criterion to stdout