Let’s start with the first example of using the “while” loop on one line of the Bash code. As the file is empty, we need to add the Bash extension in our Bash file to make it execute as a “Bash” script. It is not essential to add the extension. Your code will execute perf...
shell Bash中的While-loop子壳困境问题在于while循环是管道的一部分。在bash管道中，管道的每个元素都在...
_repeat() { #@ USAGE: _repeat string number _REPEAT=$1 while (( ${#_REPEAT} < $2 )) ## Loop until string exceeds desired length do _REPEAT=$_REPEAT$_REPEAT$_REPEAT ## 3 seems to be the optimum number done _REPEAT=${_REPEAT:0:$2} ## Trim to desired length } repeat() { ...
grep'*foo*'file# Globs in regex contextsfind . -execfoo {} && bar {} \;# Prematurely terminated find -execsudoecho'Var=42'> /etc/profile# Redirecting sudotime --format=%s sleep 10# Passing time(1) flags to time builtinwhilereadh;dossh"$h"uptime# Commands eating while loop inputali...
Let’s break down what’s going on in the Bash script you just created. Bash executes programs in order from the first line in your file to the last line. Theexprcommand can be used toevaluateBashexpressions. An expression is just a valid string of Bash code that, when run, produces ...
exit"${code}" } trap'error ${LINENO}'ERR …然后,每当创建临时文件时: 1 2 temp_foo="$(mktemp -t foobar.XXXXXX)" tempfiles+=("$temp_foo") 退出时删除$temp_foo,打印当前行号。(set -e同样会让您退出错误行为,a href="http://mywiki.wooledge.org/bashfaq/105"rel="noreferrer">尽管它带有...
ls)do cat "$Output"done# while 循环：while [ true ]do echo "loop body here..." breakdone# 你也可以使用函数# 定义函数：function foo (){ echo "Arguments work just like script arguments: $@" echo "And: $1 $2..." echo "This is a function" return 0}# 更简...
#!/usr/bin/env bash # File: whileloop.sh count=3 while [[ $count -gt 0 ]] do echo "count is equal to $count" let count=$count-1 done WHILE循环首先以while关键字开头,然后是一个条件表达式。只要循环迭代开始时条件表达式等价于true,那么WHILE循环中的代码将继续执行。当我们运行这个...
This loop generally uses a for loop construct. The condition-controlled loop repeats the execution of a section of code until a condition is met. The condition may be tested at the beginning, or the end of the loop. This loop generally uses a while loop construct. The infinite loop ...
How to wait in bash for several subprocesses to finish and return exit code !=0 when any subprocess ends with code !=0? 如何在bash脚本中等待该脚本生成的几个子进程完成并返回退出代码!=0,当任何子进程以代码结束时!= 0? 简单脚本: 1