Merge pull request #190 from codecrafters-io/TropicolX-patch-27

Revise "Redirect stderr #vz4"

Author: TropicolX

stage_descriptions/redirection-02-vz4.md

@@ -1,31 +1,64 @@
-In this stage, you'll implement support for redirecting the standard error of a command to a file.
+In this stage, you'll implement support for redirecting a command's standard error to a file.
 
-The `2>` operator is used to redirect the standard error of a command to a file.
+### The `2>` Operator
 
-Learn more about [Redirecting Stderr](https://www.gnu.org/software/bash/manual/bash.html#Redirecting-Output).
+The `2>` operator redirects the standard error of a command to a file. The standard error is where programs write error messages and diagnostics.
 
-### Tests
+In Unix, standard error is identified by the number `2`. When you write `2>`, you're explicitly redirecting file descriptor 2 (stderr) to a file.
 
-The tester will execute your program like this:
+For example:
+
+```bash
+$ cat nonexistent 2> errors.txt
+$ cat errors.txt
+cat: nonexistent: No such file or directory
+```
+
+Here, the error message is written to `errors.txt` rather than appearing in the terminal.
+
+### Standard Output Is Not Redirected
+
+The `2>` operator only redirects standard error, not standard output. Normal output still appears on the terminal:
 
 ```bash
-./your_program.sh
+$ cat existing_file nonexistent 2> errors.txt
+contents of existing file
+$ cat errors.txt
+cat: nonexistent: No such file or directory
+
+$ echo hello 2> errors.txt
+hello
+$ cat errors.txt
+$
 ```
 
-It'll then send a series of commands to your shell, executing commands and redirecting their output to a file:
+In the example above, the file contents appear in the terminal, while any error message goes to `errors.txt`.
+
+### Tests
+
+The tester will execute your program like this:
+```bash
+$ ./your_program.sh
+```
 
+It will then send a series of commands to your shell and attempt to redirect its standard error to a file:
 ```bash
 $ ls nonexistent 2> /tmp/quz/baz.md
 $ cat /tmp/quz/baz.md
 ls: nonexistent: No such file or directory
+
 $ echo 'Maria file cannot be found' 2> /tmp/quz/foo.md
 Maria file cannot be found
+$ 
+
 $ cat /tmp/bar/pear nonexistent 2> /tmp/quz/quz.md
 pear
 $ cat /tmp/quz/quz.md
 cat: nonexistent: No such file or directory
 ```
 
-The tester will check if the commands correctly execute commands and redirect their error message to a file as specified.
-
-It will also check that the file is created (if it doesn’t already exist), and that its contents match the expected output.
+The tester will verify that:
+- Commands with `2>` redirect their standard error to the specified file.
+- The specified files are created if they don't exist.
+- Standard output still appears on the terminal (not redirected).
+- Standard errors are not displayed on the terminal.