I'm having the weirdest problem on my new MacBook pro, I had the same on the old one and I thought it might have something to do with that.

On my old MacBook Pro, whenever I used the pipe char in my Terminal followed by, let's say, grep I'd get a command not found. If I then just typed grep in plain in the Terminal I'd get the standard output.

Later I discovered that the problem only occurred when I typed in the command fast:

Lets say I wanted to use tee to inherit something in a few text files. From another Terminal I'd do:

echo "-r base.txt" | tee -a development.txt texting.txt production.txt

I know this command and I'm able to type it all in ~3 seconds. It gives me:

-bash: tee: command not found

Now if I try the exact same command but really take my time typing it, lets say I use 20 seconds on typing it, then I get:

-r base.txt

This is a confirmation that the command was executed properly.

I believed something was wrong with my old MacBook. Four months ago when I bought a new Mac it was exactly the same.

I then tried to do a fresh install. I deleted the hard drive and installed macOS from scratch. The same thing still occurs.

Has anyone else experienced this problem? If so, do you have a fix?

I also tried to install another Terminal like iTerminal2, I think that's what it's called, but with the exact same problem

1 Answer 1


Your problem is actually not Terminal.app specific.

The problem is more caused by you being slow on the keys than fast actually. When you type the | (pipe) character you need to hold down the Alt-key. When you're typing fast, you're actually too slow in releasing the Alt-key.

This means that you're not actually typing a space before the next command. You're pressing Alt-Space which gives you a "non-breaking space" - which is not the same as a space, but it looks that way in the Terminal.

The "non-breaking" space is not seen by your shell as a command delimiter, but instead a part of a command or file name. And therefore you get the error that no such file or directory exists.

To solve the problem - just remember to lift your finger from the alt key before typing space.

Alternatively you can change your keyboard mapping so that Alt-Space produces an ordinary space. You can find a guide to doing that here:


  • O dear god! i fell stupid now...... so i just tested what you said and your right.... and i fell so stupid right now. Thanks #jksoegaard
    – Alexander
    Commented May 1, 2017 at 13:56

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