如何提取每行只匹配该行中特定字符的第一次出现的行？

Question

我正在编写bash shell脚本。我有一个变量，它有很多行。这里：，如何提取与第5列中的字符5匹配的每一行？

declare -a T1 echo '$input' T=$(echo -e "$input" | grep 5) echo "$T"

输入变量内容：

:: find lo(): [5] :: Current Digital = 0.00 4
:: find lo(): [6] :: Current Digital = 0.00 4
:: find lo(): [7] :: Current Digital = 0.00 5
:: find lo(): [8] :: Current Digital = 0.00 4
:: find lo(): [5] :: Current Digital = 0.00 7
:: find lo(): [6] :: Current Digital = 0.00 7
:: find lo(): [7] :: Current Digital = 0.00 15
:: find lo(): [8] :: Current Digital = 0.00 7
:: find lo(): [5] :: Current Digital = 0.00 10
:: find lo(): [6] :: Current Digital = 0.00 10
:: find lo(): [7] :: Current Digital = 0.00 10
:: find lo(): [8] :: Current Digital = 0.00 35
:: find lo(): [5] :: Current Digital = 0.00 13
:: find lo(): [6] :: Current Digital = 0.00 25
:: find lo(): [7] :: Current Digital = 0.00 13
:: find lo(): [8] :: Current Digital = 0.00 13
:: find lo(): [5] :: Current Digital = 0.00 15
:: find lo(): [6] :: Current Digital = 0.00 50
:: find lo(): [7] :: Current Digital = 0.00 16
:: find lo(): [8] :: Current Digital = 0.00 55

期望的T1变量内容：

:: find lo(): [5] :: Current Digital = 0.00 4
:: find lo(): [5] :: Current Digital = 0.00 7
:: find lo(): [5] :: Current Digital = 0.00 10
:: find lo(): [5] :: Current Digital = 0.00 13
:: find lo(): [5] :: Current Digital = 0.00 15

当前T1变量内容：

:: find lo(): [5] :: Current Digital = 0.00 4
:: find lo(): [7] :: Current Digital = 0.00 5
:: find lo(): [5] :: Current Digital = 0.00 7
:: find lo(): [7] :: Current Digital = 0.00 15
:: find lo(): [5] :: Current Digital = 0.00 10
:: find lo(): [8] :: Current Digital = 0.00 35
:: find lo(): [5] :: Current Digital = 0.00 13
:: find lo(): [5] :: Current Digital = 0.00 15
:: find lo(): [6] :: Current Digital = 0.00 50
:: find lo(): [8] :: Current Digital = 0.00 55

Answer 1

这个命令应该给出预期的输出，只要第一次出现的5总是放在括号内。

T=$(echo -e "$input" | grep '\[5\]'))