# Some knowledge on Ubuntu 了解ssh-agent Find my computer didn't have git version sudo apt install git If you can't connect ubuntu server to update package > can't connect............................ ## Learn how to change the package server. 1. change [default ubuntu server](http://tw.archive.ubuntu.com) to [go to the Ubuntu website find the address](http://free.nchc.org.tw/ubuntu/) 1-1.http://free.nchc.org.tw/ubuntu/ also can't connect,so change to http://ftp.ubuntu-tw.net/ubuntu/ ## Learn sed instruction on Ubuntu https://terryl.in/zh/linux-sed-command/#-i- sed -i 's/[target word]/[will change to word]/g' [address] >It is an instruction to replace the string or character ## Update apt package ``` ubuntu= $ sudo apt update $ sudo apt upgrade ``` >update the apt package list >upgrade is upgrade your computer ---------------- ## Ubuntu file system ### ubuntu instruction #### cat ```ubuntu= cat > [filename].md ``` >cat is create the new file. #### mv ```ubuntu= mv [old_name] [new_name] ``` >mv is to change the new name. #### rename > rename $1 $2 $3 > $1: 要被取代的關鍵字 > $2: 新的關鍵字 > $3: 檔名符合這個規則的才取代 > 把 IMG001.jpg, IMG002.jpg… 換成 img001.jpg, img002.jpg… ```ubuntu= rename IMG img IMG* ``` ##### 把所有 .htm 檔案改成 .html rename .htm .html *.htm ##### 把檔案 foo1, ..., foo9, foo10, ..., foo278. rename foo foo0 foo? ##### 改成 foo001, ..., foo009, foo010, ..., foo278. rename foo foo0 foo?? ---