I’ve got a JSON list (the value of a key-value pair containing a list of items): [ “john”, “boris”, “joe”, “frank” ] How would I convert this to a bash array, so I can iterate over them? Answer Easy Case: Newline-Free Strings The simple approach is to use jq to transform your list into a line-per-item, and read that into
Tag: shell
How to add a word at the beginning of each line BUT not when a # is present
Given a file with many ENV variables. Example: DEV.env I know the command sed “s/^/export /g” will add export at the beginning of each line. But I don’t want to do this when the first character is “#”. How can I do with sed? Answer Something like this: Alternatives:
How do you move files from one folder to the other?
I am trying to move specific files from one folder to another. Would the below work? Answer I think this can work:
Linux shell script regex match
I have a text file. I want to get lines starting with specific format. I just want to get lines that have x/x/x format. x is a number. But this regex is not working. It is always giving no match : File is : Answer Don’t use bash if you can use a better tool: But if you have to
pipe command make standard input broken
I have two processes: t1.cpp and t2.cpp. t1.cpp and t2.cpp are simplified ,I want to describe the problem easily. After compiling t1.cpp and t2.cpp. I execute them in this way ./t1 | ./t2. Problems occur! cin >> x; in t2.cpp failed! I have no chance to type from the keyboard. It seems the pipe command implements by redirecting the STDIN_FILENO.
Prevent entering duplicate records in file using Shell Script
I am creating one sh file in which user enters the roll number, name, subject name and marks. And i am storing it in one text file. Now i don’t want the user to enter the same roll number again. If he enters the same roll number it should throw an message. Here is what i have done: How to
run shell script from php as a specified user
I am trying to run a shell script from a PHP script. PHP code : my shell script : After I run the PHP code in a web server (Xampp), I got this output : Although, I haven’t set any password for the daemon user. And after I checked the current user running the PHP code I found it is
Running a program on many different computers automatically
I am new to scientific computing and am working on a project which involves running many simulations. The infrastructure with which I am provided for this is about 20 different linux machines which all share storage. What I’ve been doing so far is the horrendously inefficient task of ssh’ing into each computer individually and running the simulation programs manually. Given
Shellscript If statement returns error
I am trying to check if a file is older than 5 minutes and if that is the case I want to call another shell script which sends me a mail. check_file.sh: Error output: 3: ./check_file.sh: [1]: not found Answer Try something like:
SSH and exec channels with python shell
We have implemented a python shell for our hardware devices that solely consists of the python cmd module on embedded linux. Our (non-root) user’s shell is set to the path of this python shell in /etc/passwd and /etc/shadow. Code example below: Previously, one of our clients had used SSH.NET to issue command line commands using that library’s RunCommand function, which