Since TopAnswers already [has](https://topanswers.xyz/codegolf?q=609) a post stolen from [Martin Ender](https://codegolf.stackexchange.com/questions/55422/hello-world), let's steal another one! Your task is to write a program that copies an input taken from STDIN to STDOUT. [Link](https://codegolf.stackexchange.com/questions/62230/simple-cat-program)
| Input | Output |
# Polyglot ([W] and [GolfScript]), 0 bytes
Works in at least W and Golfscript [(GS: TIO)][TIO-k7am8gmc], likely more. Both languages push input to the stack and implicitly prints the stack at the end. Both accept input in any format and get converted to strings for output.
[TIO-k7am8gmc]: https://tio.run/##S8/PSStOLsosKPkPBCEZmcUKQJSYp5CZV1BaogcA "GolfScript – Try It Online"
# [Ahead], 4 bytes
This program will not write to STDOUT until STDIN is closed or empty.
S slurp stdin to string
U reverse string
W write string
[Try it online!][TIO-k7mzpytr]
[TIO-k7mzpytr]: https://tio.run/##S8xITUz5/z84NNzh///UgsxkBTgBAA "Ahead – Try It Online"
# [APL (Dyalog Unicode)], 1 [byte](https://codegolf.meta.stackexchange.com/a/9429/43319 "When can APL characters be counted as 1 byte each?") ([SBCS](https://github.com/abrudz/SBCS ".dyalog files using a single byte character set"))
[Try it online!][TIO-k88n336w]
`⍞` prompts from stdin, with printing to stdout happening implicitly.
[APL (Dyalog Unicode)]: https://www.dyalog.com/
[TIO-k88n336w]: https://tio.run/##SyzI0U2pTMzJT///qKO94P@j3nkgxn8FMCjgSkxKTklNAwA "APL (Dyalog Unicode) – Try It Online"