if [ -e "/path/to/file" ]; then echo "File exists." else echo "File does not exis...
在Bash Shell中,可以使用复合条件来在一个if语句中检查多个条件。复合条件主要有两种形式:逻辑与(&&)和逻辑或(||)。 1. 逻辑与(&&): - 概念:逻辑与用于同时检查多个条件...
Check Empty String 1 2 3 4 5 6 1. 2. 3. 4. 5. 6. if [[ -z "$emptyString" ]]then echo "Empty"else echo "Not Empty"fi 1. Here is a reference material from Stackoverflowhttp://stackoverflow.com/questions/3767267/check-if-file-exists 1 2 3 4 5 6 7 8 9 1...
-k file 若文件存在且设置了"sticky"位的值 -p file 若文件存在且为一已命名管道,则为真 -r file 若文件存在且可读,则为真 -s file 若文件存在且其大小大于零,则为真 -u file 若文件存在且设置了SUID位,则为真 -w file 若文件存在且可写,则为真 -x file 若文件存在且可执行,则为真 -o file ...
if [ "$name" == "Alice" ] then echo "Hello, Alice!" else echo "You are not Alice." fi Example 3: File Check #!/bin/bash file_path="/path/to/file.txt" if [ -f "$file_path" ] then echo "File exists." else echo "File does not exist." ...
- Test if the specified [d]irectory exists: [[ -d path/to/directory ]] - Test if the specified file or directory [e]xists: [[ -e path/to/file_or_directory ]] 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13.
echo "check if variable with name $1 exists"} assert_var "FOO"我们的期望是,应该检测变量FOO,同时也不存在BAR。为此,我需 浏览0提问于2020-07-01得票数 0 回答已采纳 2回答 以未实例化的变量为条件 我是Bash脚本的新手,对C-type语言有更多的经验。我已经编写了一些带有条件的脚本,用于检查未实例化...
-b file If file exists and is a block special file. -c file If file exists and is a character special file. -d file If file exists and is a directory. -e file If file exists. -f file If file exists and is a regular file. -g file If file exists and its set-group-id bit ...
Version 3.7.2 2005/11/16 作者:Mendel Cooper mail:thegrendel@theriver.com 这本书假定你没有任何脚本或一般程序的编程知识,但是如果你有相关的知识,那么你将很容易 达到中高级的水平...all the while sneaking in little snippets of UNIX? wisdom and lor... ...
if [[ -z "${1:-}" ]] then _PREPTERMUXARCH_ _INTRO_ "$@" ## [./path/systemimage.tar.gz [customdir]] Use path to system image file; install directory argument is optional. A systemimage.tar.gz file can be substituted for network install: `setupTermuxArch.bash ./[path/]...