# Usage: lines "file" mapfile -tn 0 lines < "$1" printf '%s\n' "${#lines[@]}" } 1. 2. 3. 4. 5. 示例函数(bash 3): 此方法使用的内存少于mapfile方法,并在bash3中工作,但对于较大的文件,它的速度较慢。 lines_loop() { # Usage: lines_loop "file" count=0 while IFS= read ...
# Loop from 0-100 (no variable support). for i in {0..100}; do printf '%s\n' "$i" done 循环遍历可变数字范围 替代seq。 # Loop from 0-VAR. VAR=50 for ((i=0;i<=VAR;i++)); do printf '%s\n' "$i" done 循环数组 arr=(apples oranges tomatoes) # Just elements. for elemen...
使用IF遍历文件中的每一行的BASH - loop (for) 将一行数据存储到文件中 在Flink中,如何将DataStream写到单个文件中? 如何将每个命令的stout重定向到bash中的单独日志文件? 如何在bash中加载文件和所有结果放在单独的文件中? django如何让python脚本从bash执行将stdout写到文件中? 如何使用flink打印...
/bin/bashforiin/root/*; do file $i done 其实file命令本身即可实现,主要是了解一下可以以通配符展开来生成LIST。 #file/root/* 4、计算当前所有用户的UID之和。 #!/bin/bash declare-isum=0foriin$(cut-d : -f3/etc/passwd);dosum=$[$sum+$i]doneecho"The sum of UIDs is $sum." 5、统计某...
How to do a foreach loop in bash? How to do a do-while loop in bash? How to create an infinite loop in bash? How to find if a number is odd or even in bash? How to iterate over a bash array? How to loop over each line of a file? How to iterate over a list of files?
break 2 ## break out of both while and for loops elif [ $RANDOM -lt 10000 ] then printf '"' break ## break out of the while loop fi done done echo 继续 在循环内部, continue命令通过传递任何剩余命令,立即开始循环的新迭代: for n in {1..9} ## See Brace expansion in Chapter 4 ...
我们要讨论的第一种循环是FOR循环。FOR循环遍历你指定的序列的每个元素。让我们看一个小的FOR循环示例: 代码语言:javascript 代码运行次数:0 运行 AI代码解释 #!/usr/bin/env bash # File: forloop.sh echo "Before Loop" for i in {1..3} do echo "i is equal to $i" done echo "After Loop" ...
11. Bash File Testing #!/bin/bash file="./file" if [ -e $file ]; then echo "File exists" else echo "File does not exists" fi 1. 2. 3. 4. 5. 6. 7. Similarly for example we can use while loop to check if file does not exists. This script will sleep until file does exi...
done < file.txt echo "Total number of lines are $i" Looking at the Number of Items in a Directory using Bash while Loop The counters are a crucial part of bash scripting especially to control the iterations. The example of counting the number of lines or the number of items in a direc...
In this example, the ‘for’ loop iterates over all .txt files in the current directory, echoing a statement for each file. These advanced uses of the ‘foreach’ loop in Bash open up a world of possibilities for automating tasks and processing data. As you explore these techniques, remem...