doc: add multiple missing mjs and cjs examples in fs.md

Signed-off-by: Tierney Cyren <hello@bnb.im>

doc/api/fs.md

@@ -952,6 +952,30 @@ for more details.
 The `path` may be specified as a {FileHandle} that has been opened
 for appending (using `fsPromises.open()`).
 
+```mjs
+import { appendFile } from 'node:fs/promises';
+
+try {
+	await appendFile('message.txt', 'data to append');
+} catch {
+	console.error('The file could not be appended!');
+}
+```
+
+```cjs
+const { appendFile } = require('node:fs/promises');
+
+async function appendMessagesFile () {
+	try {
+		await appendFile('message.txt', 'data to append');
+	} catch {
+		console.error('The file could not be appended!');
+	}
+}
+
+appendMessagesFile()
+```
+
 ### `fsPromises.chmod(path, mode)`
 
 <!-- YAML
@@ -964,6 +988,30 @@ added: v10.0.0
 
 Changes the permissions of a file.
 
+```mjs
+import { chmod } from 'node:fs/promises';
+
+try {
+  await chmod('my_file.txt', 0o775).then(console.log('The permissions for file "my_file.txt" have been changed!'))
+} catch {
+  console.log('The permissions for file "my_file.txt" failed to change!');
+}
+```
+
+```cjs
+const { chmod } = require('node:fs/promises');
+
+async function changeFilePermissions () {
+  try {
+    await chmod('my_file.txt', 0o775).then(console.log('The permissions for file "my_file.txt" have been changed!'))
+  } catch {
+    console.log('The permissions for file "my_file.txt" failed to change!');
+  }
+}
+
+changeFilePermissions()
+```
+
 ### `fsPromises.chown(path, uid, gid)`
 
 <!-- YAML
@@ -977,6 +1025,38 @@ added: v10.0.0
 
 Changes the ownership of a file.
 
+```mjs
+import { chown } from 'node:fs/promises'
+import { getuid, getgid } from 'node:process'
+
+const uid = getuid()
+const gid = getgid()
+
+try {
+	await chown("my_file.txt", uid, gid).then(console.log(`Successfully ran chown on my_file.txt to UID ${uid} and GID ${gid}!`))
+} catch {
+	console.log("Failed to chown my_file.txt!")
+}
+```
+
+```cjs
+const { chown } = require('node:fs/promises')
+const { getuid, getgid } = require('node:process')
+
+async function chownMyFile () {
+	const uid = getuid()
+	const gid = getgid()
+
+	try {
+		await chown("my_file.txt", uid, gid).then(console.log(`Successfully ran chown on my_file.txt to UID ${uid} and GID ${gid}!`))
+	} catch {
+		console.log("Failed to chown my_file.txt!")
+	}
+}
+
+chownMyFile()
+```
+
 ### `fsPromises.copyFile(src, dest[, mode])`
 
 <!-- YAML
@@ -2254,6 +2334,15 @@ chmod('my_file.txt', 0o775, (err) => {
 });
 ```
 
+```cjs
+const { chmod } = require('node:fs');
+
+chmod('my_file.txt', 0o775, (err) => {
+  if (err) throw err;
+  console.log('The permissions for file "my_file.txt" have been changed!');
+});
+```
+
 #### File modes
 
 The `mode` argument used in both the `fs.chmod()` and `fs.chmodSync()`
@@ -2339,6 +2428,34 @@ possible exception are given to the completion callback.
 
 See the POSIX chown(2) documentation for more detail.
 
+```mjs
+import { chown } from 'node:fs'
+import { getuid, getgid } from 'node:process'
+
+const uid = getuid()
+const gid = getgid()
+
+chown('my_file.txt', uid, gid, (err) => {
+  if (err) throw "Coudln't chown my_file.txt"
+
+  console.log(`Successfully ran chown on my_file.txt to UID ${uid} and GID ${gid}!`)
+})
+```
+
+```cjs
+const { chown } = require('node:fs')
+const { getuid, getgid } = require('node:process')
+
+const uid = getuid()
+const gid = getgid()
+
+chown('my_file.txt', uid, gid, (err) => {
+  if (err) throw "Coudln't chown my_file.txt"
+
+  console.log(`Successfully ran chown on my_file.txt to UID ${uid} and GID ${gid}!`)
+})
+```
+
 ### `fs.close(fd[, callback])`
 
 <!-- YAML