How to use stdout and stdin about neutralinojs HOT 10 CLOSED

Neutralinojs allows communication with the parent process using standard input (stdin) and standard output (stdout). This can be useful for exchanging data and commands between Neutralinojs applications and their parent processes.

Receiving Data from Parent Process (stdin):

const { stdin } = require('@neutralinojs/neu');

stdin.on('data', (data) => {
console.log(Received data from parent process: ${data});
// Process the received data as needed
});

Sending Data to Parent Process (stdout):

const { stdout } = require('@neutralinojs/neu');

// Send data to the parent process
stdout.write('Data to send to the parent process\n');

Bidirectional Communication:

const { stdin, stdout } = require('@neutralinojs/neu');

// Listen for data from the parent process
stdin.on('data', (data) => {
console.log(Received data from parent process: ${data});

// Process the received data and send a response
const response = `Processed: ${data}`;
stdout.write(response);

});

from neutralinojs.

Hello, thanks for your explanation. Currently, there is no official API to read the main process's stdin, but we can add a new function like app.readStdIn(untilEof=true/false) (or in filesystem) and a new event processStdIn in the next release (Feel free to add your suggestions for the function). I'll add this issue as a feature request.

I think some alternative methods with the current release are:

• Writing a custom API function by editing the source.
• Using CLI arguments to pass a file input, read it using Neutralino APIs, write it to a file, and read it using cat.

Thanks for posting this feature request 🎉

from neutralinojs.

Cool! I'll give it a try.

from neutralinojs.

Hello @Hill-98, do you need to communicate with the Neutralinojs framework process? For that, you can use the framework's WebSocket connection. If you need to communicate with a child process, you can use the os.spawnProcess function.

from neutralinojs.

@shalithasuranga Thanks for your reply, but it's neither of those, I need to communicate with the parent process.

like this:
cat some.txt | neutralinojs-program | grep some

Can I handle stdin and stdout?

from neutralinojs.

good one

from neutralinojs.

To send data from Neutralino to the parent process, you can write to the stdout stream. Here's an example in JavaScript:
// Send data to the parent process
function sendDataToParent(data) {
console.log(JSON.stringify(data));
}
In this example, JSON.stringify(data) converts the data into a JSON string, and console.log writes it to the stdout stream. You can call this function whenever you want to send data to the parent process.

To receive data in Neutralino from the parent process, you can read from the stdin stream. Here's an example:
// Read data from stdin
process.stdin.on('data', (data) => {
const receivedData = JSON.parse(data);
handleReceivedData(receivedData);
});

// Handle the received data
function handleReceivedData(data) {
// Process the received data
console.log('Received data from parent process:', data);
}
In this example, the process.stdin.on event listener is used to listen for data on the stdin stream. When data is received, it is parsed using JSON.parse to convert it from a JSON string to a JavaScript object. You can then handle the received data in the handleReceivedData function.
Hope this helps.

from neutralinojs.

Hello everyone, now we have added readProcessInput(readAll=true/false), writeProcessOutput(), and writeProcessError() functions. We'll release them with the next framework version soon. Thanks for reporting and discussing this 🎉

Example (testable by tomorrow with nightly):

await Neutralino.app.writeProcessOutput('Enter your name: '); 
let name = await Neutralino.app.readProcessInput();
await Neutralino.app.writeProcessOutput(`Hello ${name}...`); 

from neutralinojs.

@shalithasuranga Are these implemented correctly only on Linux?

I found that Windows didn't work. It seems to be because the Windows version works in "Window mode" instead of "Console mode". As far as I understand, one Windows program cannot implement both modes at the same time, so is it possible to provide another binary for Windows separately? (Like: neutralino-win_x64_console.exe)

from neutralinojs.

Hey @Hill-98, thanks for posting this info. Mm. yeah, according to internet documentations, I also found the same thing you've mentioned about Windows executables. The issue is that I couldn't test this feature on Windows since our Azure sponsorship was terminated. Looks like we need to get some help from a contributor until I re-apply for the Azure sponsorship. Thanks 🎉

from neutralinojs.