STDIN breaks after refreshing piped executables

• nodemon -v: ^1.19.4
• node -v: v13.3.0
• Operating system/terminal environment: Windows/Git Bash
• Using Docker? What image:
• Command you ran: nodemon -e js --exec “node …\external\secret.js | node server.js”

Expected behaviour

Run consistently, at least always give me an error.

Actual behaviour

Somehow, I get trapped getting errors if my code produces an error in a refresh. Sometimes, not consistent with any other events that I can tell, I keep getting the error below every time I try and refresh. I can open a new shell terminal, I can close/reopen all shell terminals on the system, but every time I try and run the command it spits out this error. If I wait for another 5-10min, it seems to just go away on its own.

I’m getting an error from node’s built-in fs module: internal/fs/utils.js:227 throw err; Error: EOF: end of file, read errno: -4095, syscall: ‘read’, code: ‘EOF’

Steps to reproduce

Run a express server that blocks on being initialized from data from stdin, then add a throw at the beginning, save/refresh through nodemon, remove the throw and attempt to run again. Like I said this seems to be entirely unpredictable; so sometimes I’ll have to add/remove the throw a couple times or restart my shell.

// Source file
const objectToWrite = { somedata:'someval' }
process.stdout.write(JSON.stringify(objectToWrite));
process.stdout.end('\n');
// I've messed around with various STDIO implementations
// and it doesn't seem to have any affect the error.

// Receiving file
const fs = require('fs')
let envTmp = fs.readFileSync(0).toString();
// breaks on fs utils here ^
	envTmp = JSON.parse(envTmp);

---

Dump Text

[nodemon] 1.19.4 [nodemon] to restart at any time, enter rs [nodemon] watching dir(s): . [nodemon] watching extensions: js

node: v13.3.0 nodemon: 1.19.4 command: C:\Program Files\nodejs\node.exe bin\nodemon.js -e js --exec node …\secret.js | node server.js --dump OS: win32 x64

{
  run: false,
  required: false,
  timeout: 1000,
  options: {
    exec: 'node ..\\secret.js | node server.js',
    dump: true,
    ignore: [
      '**/.git/**',
      '**/.nyc_output/**',
      '**/.sass-cache/**',
      '**/bower_components/**',
      '**/coverage/**',
      '**/node_modules/**',
      re: /.*.*\/\.git\/.*.*|.*.*\/\.nyc_output\/.*.*|.*.*\/\.sass\-cache\/.*.*|.*.*\/bower_components\/.*.*|.*.*\/coverage\/.*.*|.*.*\/node_modules\/.*.*/
    ],
    watch: [ '*.*', re: /.*\..*/ ],
    ignoreRoot: [
      '**/.git/**',
      '**/.nyc_output/**',
      '**/.sass-cache/**',
      '**/bower_components/**',
      '**/coverage/**',
      '**/node_modules/**'
    ],
    restartable: 'rs',
    colours: true,
    execMap: { py: 'python', rb: 'ruby', ts: 'ts-node' },
    stdin: true,
    runOnChangeOnly: false,
    verbose: false,
    signal: 'SIGUSR2',
    stdout: true,
    watchOptions: {},
    execOptions: {
      script: null,
      exec: 'node ..\\secret.js | node server.js',
      args: [],
      scriptPosition: null,
      nodeArgs: undefined,
      execArgs: [],
      ext: 'js',
      env: {}
    },
    monitor: [
      '*.*',
      '!**/.git/**',
      '!**/.nyc_output/**',
      '!**/.sass-cache/**',
      '!**/bower_components/**',
      '!**/coverage/**',
      '!**/node_modules/**'
    ]
  },
  load: [Function (anonymous)],
  reset: [Function: reset],
  lastStarted: 0,
  loaded: [],
  watchInterval: null,
  signal: 'SIGUSR2',
  command: {
    raw: {
      executable: 'node ..\\secret.js | node server.js',
      args: []
    },
    string: 'node ..\\secret.js | node server.js'
  }
}

[josh-hemphill]

I just refactored my code to wrap the whole thing in a .then() to use the normal process.stdin and now it doesn’t seem to have any issues.

Does nodemon try and detect if stdin is being used? Maybe it just missed fs.readFileSync(0)?

[remy]

Can you provide a pared down code sample to run? Otherwise I can’t reproduce.