Update README.md

Added instructions for making the CLI read from `stdin`

Author: GlitchedPolygons

README.md

@@ -110,6 +110,26 @@ Append `--algorithm=chachapoly` at the end to use the [ChaCha20-Poly1305](https:
 
 `pwcrypt d "EwAAAAQAAAAAAAQAAgAAAFYjNGlNEnNMn5VtyW5hvxnKhdk9i" "Decryption Password 123 !!!"`
 
+---
+
+#### stdin / stdout / pipes
+
+Since [v4.3.0](https://github.com/GlitchedPolygons/pwcrypt/releases/tag/4.3.0) it is now possible to make the pwcrypt CLI read the input from `stdin`.
+
+To do so, just pass `-` as the input parameter after the `e` or `d` argument. The `--file=/output/file/path/here` still works (and if it's not set, the output will be written to `stdout`).
+
+For example, to compress and encrypt a whole directory you could pipe the result of `tar` into `pwcrypt`. Such a command would look like this:
+
+`tar -czf - -C /my/directory/to/compress/and/encrypt . | pwcrypt e - "SuperSafeEncryptionPassword123" --file=result.tar.gz.pwcrypt --compression=0`
+
+The same thing can also be done using the `>` redirection (if you don't wanna type out the `--file=` argument).
+
+`tar -czf - -C /my/directory/to/compress/and/encrypt . | pwcrypt e - "SuperSafeEncryptionPassword123" --compression=0 > result.tar.gz.pwcrypt`
+
+To decrypt the above example encrypted archive one would use the following command:
+
+`cat result.tar.gz.pwcrypt | pwcrypt d - "SuperSafeEncryptionPassword123" | tar -xzf -`
+
 ### Files instead of strings
 
 The pwcrypt CLI supports encrypting/decrypting files instead of strings too: <p>