參數若不足則是空白,但還是會執行完,所以較難找維修
若沒有x權限 就開1個bash執行(用程式執行他,就不需要x權限)
bast 檔名
變數: 只有自己的shell看的見
環境變數: 與自己有關的shell看的見
$_ (底線為上一個設定的變數)
每個指令都會回傳一個結束碼
常見:
0=正常結束
1=語法錯誤
2=資料不存在
127=指令不存在
echo $? (取得前一個指令結束碼)
exit(n) n=0-255 (超過就是取%256餘數,含0)
mount
df -h
declare -i x=77 (宣告為整數77)
x=hello (附字串值給x)
x=0 (還是整數型態)
若筆記內有發現錯誤隨時可以登入後在這邊留言~
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