Why you should not use the || and && operators instead of a Bash If Statement? Detailed Examples & FAQ How to check if a variable exists or is “null”? How to check if a file exists? How to check if a directory exists? How to check if a command succeeds or failed? How to do...
if [ ! -z err−o!−eapk ]; then 会报出-e无法找到的错误; 而if [ ! -z err]||[!−eapk ]; then 没问题; 整数比较 : -eq 等于,如:if [ "a"−eq"b" ] -ne 不等于,如:if [ "a"−ne"b" ] -gt 大于,如:if [ "a"−gt"b" ] -ge 大于等于,如:if [ "a"−ge...
Q2. Can I use the if statement to check the existence of a file or directory? A2. Absolutely. Bash provides conditionals like -e, -f, and -d to check the existence of a file or directory, along with other conditionals to check for readability, writability, and executability. Q3. Can ...
9. Bash if / else / fi statements 9.1. Simple Bash if/else statement Please note the spacing inside the [ and ] brackets! Without the spaces, it won't work! #!/bin/bash directory="./BashScripting" # bash check if directory exists ...
# File: simpleif.sh echo "Start program" if [[ $1 -eq 4 ]] then echo "You entered $1" fi echo "End program" First this program will print “Start program”, then the IF statement will check if the conditional expression[[ $1 -eq 4 ]]is true. It will only be true if you ...
ad@DESKTOP-3KE0KU4:~$ ./test1.sh File exists Explanation:In the exercise above,The variable 'file_to_check' holds the name of the file we want to check. The "if" statement checks if the file exists using the -e test operator. If the file exists, it prints "File exists" and ...
and elif. Then we'll look at a few of the "primary" operators you can leverage in a conditional statement such as = for string equality, -eq for numeric equality, and -e to check if a file exists. After that, we'll use conditional statements to create a function that asserts that ...
and elif. Then we'll look at a few of the "primary" operators you can leverage in a conditional statement such as = for string equality, -eq for numeric equality, and -e to check if a file exists. After that, we'll use conditional statements to create a function that asserts that ...
How to find if a number is odd or even in bash? You can use a bash for loop with a nested bash if statement using a bash arithmetic expansion with the module operator. for x in {1..5}; do if (( x % 2 )); then echo "\$x=$x is an odd number" else echo "\$x=$x is...
f FILE—— 如果 ref="https://linuxize.com/post/bash-check-if-file-exists/">FILE 存在,并且是常规文件(不是目录或设备什么的) ,则为真。 结论 if、if..else 和if..elif..else 语句让我们能够基于不同的判断条件来控制 Bash 脚本中逻辑语句的执行。 如果你有任何疑问或反馈,请随时发表评论。