This construction replaces all occurrences of';'(the initial//means global replace) in the stringINwith' '(a single space), then interprets the space-delimited string as an array (that's what the surrounding parentheses do). 这个构造替换了字符串中所有出现的“;”(初始//意味着全局替换),然后...
The part that split the string is here: IFS=';' read -ra my_array <<< "$my_string" Let me explain it to you. IFS determines the delimiter on which you want to split the string. In my case, it’s a semi colon. It could be anything you want like space, tab, comma or even ...
lastElement=$(echo $myString | grep -oE '[^ ]+$') echo "The last element is: $lastElement" Output 1 2 3 The last element is: spaces In this example, the string "some text with spaces" contained text separated by spaces. The grep command is used with the -oE parameters to ge...
Let’s break down what’s going on in the Bash script you just created. Bash executes programs in order from the first line in your file to the last line. Theexprcommand can be used toevaluateBashexpressions. An expression is just a valid string of Bash code that, when run, produces a...
In Bash, you can create an array by simply assigning values to a variable using parentheses( ). Each value is separated by a space. Here’s an example: # Creating an array myArray=("Bash" "Array" "Of" "Strings") # Printing the entire array ...
string integer expression file testexits with the status determined by EXPRESSION. Placing the EXPRESSION between square brackets ([and]) is the same as testing the EXPRESSION withtest. To see the exit status at the command prompt, echothe value “$?” A value of 0 means the expression evalu...
let "instances = ${#P_array[*]} - 2" # 计算元素个数, 至少为1. # 为什么减1? echo "$instances instance(s) of this script running." echo "[Hit Ctl-C to exit.]"; echo sleep 1 # 等一下. bash $0 # 再来一次, Sam. exit 0 # 没必要; 脚本永远不会运行到这里. ...
Bash cannot return values, whether a single value or an array, but it can return a status (the same as other programs). However, there are multiple
Note that a negative offset must be separated from the colon by at least one space to avoid being confused with the :- expansion. 即,${parameter:offset:length}表达式从parameter变量值的第offset个字符开始,一直获取length个字符,得到一个子字符串,会包括第offset个字符自身。
csv 将Bash数组转换为分隔字符串你把arrayids通过一个空格合并后的字符串构建转移到一个类型为string的新...