$ ./empty_string.sh "go on" ./empty_string.sh: line 5: test: go: binary operator expected ./empty_string.sh: line 9: [: go: binary operator expected (3) -n "$1": Quote : not empty. $ ./empty_string.sh (1) -n $1 : No quote: not empty. (2) -z $1 : No quote: ...
/bin/sha=10b=20if[ $a !=$b ]thenecho"$a != $b : a is not equal to b"elseecho"$a != $b: a is equal to b"fiif[ $a -lt100-a $b -gt15]thenecho"$a -lt 100 -a $b -gt 15 : returns true"elseecho"$a -lt 100 -a $b -gt 15 : returns false"fiif[ $a -lt100...
-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"b" ] -lt 小于,如:if [ "a"−lt"b" ] -le 小于等于,如:if [ "a"−le"b" ] < 小于(需要双括号),如:(("a"<"b")) <...
-n is one of the supported bash string comparison operators used for checking null strings in a bash script. When -n operator is used, it returns true for every case, but that’s if the string contains characters. On the other hand, if the string is empty, it won’t return true. -...
Exercise 1: Write a bash shell script that checks the length of the string provided to it as an argument. If no argument is provided, it prints 'empty string'. Exercise 2: Write a shell script that checks whether a given file exists or not. You can provide the full file path as the...
If the string is empty, the script prints "The string is empty" using the "echo" command. If the string is not empty, the script prints "The string is not empty". The "fi" statement marks the end of the "if" block. 5.
An OR list has the form command1 || command2 command2 is executed if and only if command1 returns a non- zero exit status. The return status of AND and OR lists is the exit status of the last command executed in the list. Compound Commands A compound command is one of the following...
String comparison with test Command Here are some string comparison examples using the test command. Check if the string is not empty The-nflag checks if the string length is non-zero. It returns true if the string is non-empty, else it returns false if the string is empty: ...
可以在 Bash、PowerShell和 Windows 命令行界面(Cmd)脚本语言中执行 Azure CLI命令。 但是,编写脚本时存在细微的差异。 在本教程步骤中,了解如何为所有三种脚本语言创建第一个Azure 存储帐户和格式参数值。 先决条件 已完成准备环境的先决条件。 可以访问在资源组级别具有contributor或更高权限的资源组。
拖入浏览器,方可跳转到指定锚点 https://www.gnu.org/software/bash/manual/bash.html#:~:text=%5D-,3.2.5.2%20Conditional%20Constructs,-if Shell 中test 单中括号[\] 双中括号[[]] test/[ ]判断 Linux test Command Tutorial for Beginners (with Examples) (how...