20

When using Vim to read from stdin, it prints a informative message:

$ echo foo | vim -
Vim: Reading from stdin...

$

This is just an example. The actual use doesn't allow shell constructs. vim <(echo foo) is not an option.

Can I suppress that using only Vim options and/or vimrc settings?

In case you do need to know what this is for, I'm trying to use Vim for reading manpages (shameless plug). GNU man doesn't allow shell constructs in MANPAGER, and by using ftplugin/man.vim and other things, I have successfully managed to have a comfortable experience using just MANPAGER="vim -". The last remaining annoyance is the unsightly message printed after every manpage that I viewed.

chicks
  • 332
  • 1
  • 5
  • 13
muru
  • 24,838
  • 8
  • 82
  • 143

4 Answers4

12

The answer to your exact question:

Can I suppress that using only Vim options and/or vimrc settings?

is: no, it's not possible because of the following part of the code

    if (read_stdin)
    {
#ifndef ALWAYS_USE_GUI
        mch_msg(_("Vim: Reading from stdin...\n"));
#endif

which means that if you give - as argument to vim, then it'll mechanically show that message.

though, as a work around, if you use a file redirection instead of the - argument you'll get rid of the message:

echo "foo" | vim < /dev/tty

and here's an example of MANPAGE setting that just works™ (taken from the intertubes):

export MANPAGER='bash -c "vim -MRn -c \"set ft=man nomod nolist nospell nonu\" -c \"nm q :qa!<CR>\" -c \"nm <end> G\" -c \"nm <home> gg\"</dev/tty <(col -b)"'
zmo
  • 366
  • 2
  • 7
  • 2
    When is ALWAYS_USE_GUI defined, do you know? – muru Sep 09 '15 at 08:46
  • 2
    see feature.h (it's done when ALWAYS_USE_GUI is not defined, so basically for all unix versions). – Christian Brabandt Sep 09 '15 at 08:54
  • 2
    I cannot get the workaround echo "foo" | vim < /dev/tty work. Doing it gives [2]+ Stopped echo "foo" | vim < /dev/tty. – Léo Léopold Hertz 준영 Jul 01 '16 at 05:51
  • 2
    Like @LéoLéopoldHertz준영, the tty trick didn't work for me (gvim gives an empty document, vim gets real confused with the keyboard inputs, but at least it doesn't receive a SIGSTOP). I've had more luck with echo "foo" | gvim /dev/stdin (although the non-GUI vim will still issue a complaint about that: Vim: Warning: Input is not from a terminal). – Adam Katz Jan 14 '17 at 01:38
  • The OP was asking explicitly about vim and not gvim. There are subtle differences between the two, as you can see in the quoted snippet. Also, using tricks involving chardev files (i.e. /dev/tty) might depend on the terminal you're using, some terminals not respecting the standards. – zmo Jan 14 '17 at 10:10
  • @LéoLéopoldHertz준영 -- zmo has illustrated why I didn't provide a new answer. – Adam Katz Jan 15 '17 at 20:32
  • Great answer, but I'd like to clarify for @LéoLéopoldHertz준영 and others wondering why wouldn't echo test | vim < /dev/tty work. As you can read in https://stackoverflow.com/questions/8514735/what-is-special-about-dev-tty, /dev/tty stands for the standard input for the currently running process, and is different for each new process. In case of echo test ... /dev/tty corresponds to the terminal's standard input, which is essentially your keyboard, and thus the trick doesn't work. If you, for example, execute that line from a standalone process, it will work as it works with MANPAGER – Alexander Solovets Oct 25 '18 at 08:13
  • 2
    Well, forget my previous message. The trick in the answer is in <(col -b) part. That's essentially some sophisticated version of cat for printing man pages, and you can finally get rid of the vim's message with echo test | vim < /dev/tty <(cat> – Alexander Solovets Oct 25 '18 at 08:37
11

Starting with Vim 8.0.1308 (Nov 2017), you can use the "--not-a-term" option with "quit":

$ echo hello | vi - --not-a-term -esc '%p|q!'
hello

Or with "exit":

$ echo hello | vi - --not-a-term -esc 'x!/dev/stdout'
hello

http://github.com/vim/vim/issues/1552

Zombo
  • 1
  • 5
  • 18
  • As is, this is equivalent to cat, but it can still be useful for applying Vimscript to the input, e.g. +'runtime! syntax/2html.vim' to export highlighted text as styled HTML (assuming deduced or specified filetype). There are a few options other than the ones mentioned so far; the first that comes to mind is using mktemp to store the command's output and using this as Vim's input. You could add Vim's redirection and shell commands to 'paste' the command result into the buffer, but this takes some more work. (Vim script files can automate lengthy invocations instead of using aliases.) – John P Oct 30 '17 at 10:57
  • It might be possible to edit/paste output from a socket, which could be really useful if it were true. I still say the best option is a temp file, unless there are caveats worse than those for the accepted answer. For a given shell though, there may be an existing alias/builtin/syntax that simplifies some part of this process, like those listed in the manpage for zshmisc (redirections, etc.) One more - maybe you can escape the input and supply it as an argument after an argument entering insert mode, so it parses as though typed? – John P Oct 30 '17 at 11:17
  • I see --not-a-term in Vim 7.4.1689 in Ubuntu 16.04 (but not 7.4.8056 on a Mac), but it doesn't suppress the message. – Dennis Williamson Dec 11 '18 at 23:48
  • @DennisWilliamson See the changelog by :help version8.txt. --not-a-term option itself was added in 7.4.1419 and its behavior was changed to also suppress the Reading from stdin... message in 8.0.1308. (By the way, the N files to edit message is also be suppressed from 8.1.1258) – ynn Oct 20 '19 at 15:13
2

In Vim, this issue has been addressed in 234d162 commit (>=v8.0.1387).

Solution: Don't show the message with --not-a-term was used.

So the message is only displayed when user hasn't redirected the stdin.

Similar issue has been addressed in the recent version of Neovim (>=v0.2.2-dev) which you could use instead of Vim.

Once NVim v0.2.2 is released, you should be able to run:

$ echo foo | nvim -

without having the message.

kenorb
  • 18,433
  • 18
  • 72
  • 134
1

  1. With vim of version 8.0.1387 and newer you can use --not-a-term option.

  2. For older version use the following trick: $ echo foo | bash -c 'vim < /dev/tty <(cat)'

The first argument /dev/tty somehow tricks Vim to think the input comes from the keyboard. I guess, that's because isatty(3) returns True for that file. And the second argument simply passes-through everything from its standard input to Vim's standard input. Finally, bash -c prefix is required for the special construct <(...) to work if the shell doesn't support it. In bash the original solution can be simplified to $ echo foo | vim < /dev/tty <(cat)

Alexander Solovets
  • 143
  • 4