Code files

Chapter03/working-with-files/asynchronous-file-operations/null-byte-remover.js

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+'use strict'
+
+setInterval(() => process.stdout.write('.'), 10).unref()
+
+const fs = require('fs')
+const path = require('path')
+const cwd = process.cwd()
+
+fs.readFile(path.join(cwd, 'file.dat'), (err, bytes) => {
+  if (err) { console.error(err); process.exit(1); }
+  const clean = bytes.filter(n => n)
+  fs.writeFile(path.join(cwd, 'clean.dat'), clean, (err) => {
+    if (err) { console.error(err); process.exit(1); }
+    fs.appendFile(
+      path.join(cwd, 'log.txt'),
+      (new Date) + ' ' + (bytes.length - clean.length) + ' bytes removed\n'
+    )
+  })
+})