This way, to test if a number, n, is prime for numbers greater than 3, we perform a series of steps: check if n is divisible by 2 or 3 check if n is divisible by numbers of the form 6k-1 or 6k+1 that are less than or equal to the square root of n If n satisfies neither...
在下面的示例中,我们包含了一个 if-else 语句,用于检查并打印出 1 到 7 之间的偶数和奇数。 #!/bin/bash for (( n=1; n<=7; n++ )) do # Check if the number is even or not if (( $n%2==0 )) then echo "$n is even" else echo "$n is odd" fi done 使用“Continue”语句 “...
If the $count variable is zero, the grep output was empty, passed to the wc-1 because the pattern was not matched. The script then outputs the message No match found. to the console using the echo command. That’s all about Bash check if grep result is empty. Was this post helpful?
您可以在 C 风格的 for 循环中包含条件语句。在下面的示例中,我们包含了一个 if-else 语句,用于检查并打印出 1 到 7 之间的偶数和奇数。 #!/bin/bashfor(( n=1; n<=7; n++ ))do# Check if the number is even or notif(($n%2==0))thenecho"$nis even"elseecho"$nis odd"fidone 使用“Co...
1 done } cmd_with_process() { $1 & pid=$! process $pid & wait $pid if [ $? -eq 0 ]; then echogreen "[ok]" else echo_red "[fail]" fi } case $ in check_cmd) shift cmd_with_process"$*" ;; *) echo_blue "Usage $0 [check_services|check_cmd]" echo_yellow "For...
在脚本中,if语句的不同部分通常是良好分隔的。以下是一些简单的例子: 7.1.1.3. 检查文件 第一个例子检查一个文件是否存在: anny ~> msgcheck.shanny ~> 7.1.1.4. 检查shell选项 加入到你的Bash配置文件中去: # These lines will print a message if the noclobber option is set: ...
exec 是一个在Bash Shell脚本中使用的命令，它允许您替换当前进程的内容，包括进程ID和文件描述符。使用...
if [ ${#array1[@]} -eq 0 ]; then This time, we got the size of the array and test it with the number zero. Let's see both methods with sample examples. Check empty bash array with string comparison We are going to use two elements to check if bash array is empty or not. On...
This script Checks for exactly 2 arguments with specific conditions or a single argument that must be "status" and it uses regex (^[0-9]+$) to check if the first argument is a number. If we want to print all the arguments passed to script as well, then we can use another special ...
if [ $1 -gt 10 ]; then echo "The number is greater than 10."else echo "The number is not greater than 10."fi 在shell中运行脚本并传递参数：bash check_number.sh 15，将输出The number is greater than 10.这只是一些bash用法的简单示例，bash还提供了许多其他功能和命令，可根据具体需求进行...