使用 Bash 从简单的 linux 脚本编辑变量

Question

I have that simple script there, what I would like to do is edit that A variable to output 5 when I run ./prA.sh from bash.

But I would like to know how to do it via command line, or bash. I don't want to edit the Script using Vi or any other editor.

Answer 1

If I understood your question right, you have some options to solve your problem, here I will show two.

$ chmod +x test.sh 

$ cat test.sh 
#!/bin/bash
A=${1}      # here you will receive the "aloha", showed in example below
echo $A

$ ./test.sh "aloha"
aloha

$ bash -x test.sh "aloha"   # debugging bash scripts easily
+ A=aloha
+ echo aloha
aloha

# you can see in terminal A still empty, because you just 
# passed "aloha" as argument/parameter to the bash script
$ echo $A

$ export A="aloha" # if you want A to be defined in terminal, export it
$ echo $A # now you have value directly in terminal
aloha

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