LINUX NL指令

介紹

nl指令用來檢視檔案並加上行號。

語法

nl [options] [files]

常用的options

-b [a|t|n|p R]  Prepend numbers to all lines (a), nonblank lines (t), no lines (n), or only lines that contain regular expression R. (Default=a)

-v N            Begin numbering with integer N. (Default=1)

-i N            Increment the number by N for each line, so for example, you could use odd numbers only (-i 2) or even numbers only (-v 2 -i 2). (Default=1)

-n [ln|rn|rz]   Format numbers as left-justified (ln), right-justified (rn), or right-justified with leading zeros (rz). (Default=ln)

-w N            Force the width of the number to be N columns. (Default=6)

-s S            Insert string S between the line number and the text. (Default=Tab)

範例

你可以檢視檔案並加上行號：

⤍ cat mytext
Once upon a time, there was
a little operating system named
Linux, which everybody loved.

⤍ nl mytext
     1  Once upon a time, there was
     2  a little operating system named
     3  Linux, which everybody loved.