using default value of $2, returns true if response starts with y or Y or is empty string local DEFAULT=yes if [ "$2" ]; then local DEFAULT="$( toLowerCase "$2" )"
bash command if a string is not empty examples of the check when DiskInternals can help you Are you ready? Let's read! Variables that are set and not empty A variable is either defined or not defined. However, when a variable is defined but has no value, then the variable is “Not ...
urlencode.sh / urldecode.sh - URL encode/decode quickly on the command line, in pipes etc. urlextract.sh - extracts the URLs from a given string arg, file or standard input url_extract_redirects.sh - extracts the URLs from a given string arg, file or standard input, queries each one ...
The distinction between unset and "set to the empty string" is essential in situations where the user has to specify an extension, or additional list of properties, and that not specifying them defaults to a non-empty value, whereas specifying the empty string should make the script use an ...
I have had so many instances where I wanted to check if a value was present in an array or not. You can probably iterate over all the array items and check it individually, but what if I give you the red pill? I have created an array in which there is a stringasdfand I want to...
The " ${my_array[*]} " syntax expanded the array into a single string with every element separated by a space, and the * wildcard characters indicated that the search value could appear at any position in the string. If the search value was found, the if statement printed the Array ...
if [ -z ${var+x} ]; then echo "var is unset"; else echo "var is set to '$var'"; fi 参考:https://stackoverflow.com/questions/3601515/how-to-check-if-a-variable-is-set-in-bash 6、换算秒为分钟、小时 代码语言:javascript 复制 #!/bin/bash a=60100 swap_seconds () { SEC=$1...
delete the shortest part that matches and return the rest ${variable%%pattern} # if the pattern matches the end of the variable's value, delete the longest part that matches and return the rest ${variable/pattern/string} # the longest match to pattern in variable is replaced by string. On...
[[${string1}>${string2}]] 算术运算符 如果两个数相等,则返回true: 代码语言:javascript 复制 [[${arg1}-eq ${arg2}]] 如果数字不相等,则返回true: 代码语言:javascript 复制 [[${arg1}-ne ${arg2}]] 如果arg1小于arg2,返回true 代码语言:javascript ...
Check Devices Checking wireless connection Along with many other things, the list above will be the commands we will discuss. Commands Creating folders Creating folders can be done simply in the file manager nautilus by right clicking and selecting 'Create Folder', but if you want to do th...