@zekjur Dafuq.

Interestingly enough, all the numbers are in the clipboard, pasting them in Neovim works fine. Pasting them directly into the shell command line works too. It's just the input redirection somehow?

It's not cat either, dd does the same thing 🤔

And yeah, 4096 bytes (including the newline), just like you. (Gnome Terminal, bash, Wayland)

@scy @zekjur It's the expected behavior of a tty on Linux in canonical mode:

From termios(3):

> The maximum line length is 4096 chars (including the terminating newline character); lines longer than 4096 chars are truncated.

@scy @zekjur To prove it, you can disable the canonical mode for the tty with `stty -icanon` before pasting (and restore the previous tty settings afterwards). The canonical mode is what allows you to edit the input line by handling special characters such as backspace (erase), Ctrl-W (werase), or Ctrl-D (eof).

stty_saved=$(stty -g)
stty -icanon
cat > /tmp/wat.txt
<copy&paste the 2000 numbers, hit return, then kill it with Ctrl-C>
stty "$stty_saved"
wc /tmp/wat.txt

@syphdias @scy @zekjur With the heredoc syntax, input will be processed by readline in the shell. That also means the whole input is buffered by the shell before the process for the `cat` command is even forked. Your shell will create a temporary file and redirect that to stdin instead of reading directly from the tty.

You can check the tty settings from a different terminal window to observe this. In the first window, get the pty device with the `tty` command. In the second terminal window, check with `stty -a -F /dev/pts/XX` while the first terminal window is in the shell prompt, running cat, running cat with heredoc, etc. Whenever readline is processing input, the tty will be in non-canonical input mode indicated by '-icanon'.