doc: add example for execFileSync method and ref to stdio

Added an example to the `execFileSync` method. This demonstrates how to
handle exceptions and access the stderr and stdio properties that are
attached to the `Error` object in a `catch` block.

Added a link to the detailed stdio section nested under
`child_process.spawn()` from each child_process sync method option
description.

Fixes: #39306
PR-URL: #39412
Reviewed-By: James M Snell <[email protected]>
Reviewed-By: Gireesh Punathil <[email protected]>
Reviewed-By: Matteo Collina <[email protected]>
Reviewed-By: Antoine du Hamel <[email protected]>

doc/api/child_process.md

@@ -921,7 +921,8 @@ changes:
   * `input` {string|Buffer|TypedArray|DataView} The value which will be passed
     as stdin to the spawned process. If `stdio[0]` is set to `'pipe'`, Supplying
     this value will override `stdio[0]`.
-  * `stdio` {string|Array} Child's stdio configuration. `stderr` by default will
+  * `stdio` {string|Array} Child's stdio configuration.
+    See [`child_process.spawn()`][]'s [`stdio`][]. `stderr` by default will
     be output to the parent process' stderr unless `stdio` is specified.
     **Default:** `'pipe'`.
   * `env` {Object} Environment key-value pairs. **Default:** `process.env`.
@@ -962,6 +963,34 @@ If the process times out or has a non-zero exit code, this method will throw an
 function. Any input containing shell metacharacters may be used to trigger
 arbitrary command execution.**
 
+```js
+const { execFileSync } = require('node:child_process');
+
+try {
+  const stdout = execFileSync('my-script.sh', ['my-arg'], {
+    // Capture stdout and stderr from child process. Overrides the
+    // default behavior of streaming child stderr to the parent stderr
+    stdio: 'pipe',
+
+    // Use utf8 encoding for stdio pipes
+    encoding: 'utf8',
+  });
+
+  console.log(stdout);
+} catch (err) {
+  if (err.code) {
+    // Spawning child process failed
+    console.error(err.code);
+  } else {
+    // Child was spawned but exited with non-zero exit code
+    // Error contains any stdout and stderr from the child
+    const { stdout, stderr } = err;
+
+    console.error({ stdout, stderr });
+  }
+}
+```
+
 ### `child_process.execSync(command[, options])`
 
 <!-- YAML
@@ -991,7 +1020,8 @@ changes:
   * `input` {string|Buffer|TypedArray|DataView} The value which will be passed
     as stdin to the spawned process. If `stdio[0]` is set to `'pipe'`, Supplying
     this value will override `stdio[0]`.
-  * `stdio` {string|Array} Child's stdio configuration. `stderr` by default will
+  * `stdio` {string|Array} Child's stdio configuration.
+    See [`child_process.spawn()`][]'s [`stdio`][]. `stderr` by default will
     be output to the parent process' stderr unless `stdio` is specified.
     **Default:** `'pipe'`.
   * `env` {Object} Environment key-value pairs. **Default:** `process.env`.
@@ -1069,7 +1099,8 @@ changes:
     this value will override `stdio[0]`.
   * `argv0` {string} Explicitly set the value of `argv[0]` sent to the child
     process. This will be set to `command` if not specified.
-  * `stdio` {string|Array} Child's stdio configuration. **Default:** `'pipe'`.
+  * `stdio` {string|Array} Child's stdio configuration.
+    See [`child_process.spawn()`][]'s [`stdio`][]. **Default:** `'pipe'`.
   * `env` {Object} Environment key-value pairs. **Default:** `process.env`.
   * `uid` {number} Sets the user identity of the process (see setuid(2)).
   * `gid` {number} Sets the group identity of the process (see setgid(2)).