linux awk获取倒数某一列

结果可以从man手册找到

• -F参数 -F fs –field-separator fs Use fs for the input field separator (the value of the FS predefined variable).-F参数指定用于分割的字符或者是字符串。
• Fields As each input record is read, gawk splits the record into fields, using the value of the FS variable as the field separator.If FS is a single character, fields are separated by that character. If FS is the null string, then each individual character becomes a separate field.
• NF（代表的是被分割后的字段总数） The variable NF is set to the total number of fields in the input record.

以下字段为例：
| `- 17:0:0:0 sdl 8:176 active ready running

• 获取以空格为分隔符，倒数第一列数据

echo'| `- 17:0:0:0  sdl  8:176  active ready running'|awk -F " "'{print $NF}'

结果为：running

• 获取以空格为分隔符，倒数第二列数据

echo'| `- 17:0:0:0  sdl  8:176  active ready running'|awk -F " "'{print $(NF-1)}'

结果为：ready