Terminal prompt not wrapping correctly

Question

I have an issue where if I type in very long commands in bash the terminal will not render what I'm typing correctly. I'd expect that if I had a command like the following:

username@someserver ~/somepath $ ssh -i /path/to/private/key
[email protected]

The command should render on two lines. Instead it will often wrap around and start writing over the top of my prompt, somewhat like this:

[email protected] -i /path/to/private/key

If I decide to go back and change some argument there's no telling where the cursor will show up, sometimes in the middle of the prompt, but usually on the line above where I'm typing.

Additional fun happens when when I Up to a previous command. I've tried this in both gnome-terminal and terminator and on i3 and Cinnamon. Someone suggested it was my prompt, so here that is:

\[\033[01;32m\]\u:\[\033[01;34m\] \W\033[01;34m \$\[\033[00m\]

Ctrll, reset, and clear all do what they say, but when I type the command back in or Up the same things happens.

I checked and checkwinsize is enabled in bash. This happens on 80x24 and other window sizes.

Is this just something I learn to live with? Is there some piece of magic which I should know? I've settled for just using a really short prompt, but that doesn't fix the issue.

Answer 1

Non-printable sequences should be enclosed in \[ and \]. Looking at your PS1 it has a unenclosed sequence after \W. But, the second entry is redundant as well as it repeats the previous statement "1;34".

\[\033[01;32m\]\u:\[\033[01;34m\] \W\033[01;34m \$\[\033[00m\]
                  |_____________|               |_|
                         |                       |
                         +--- Let this apply to this as well.

As such this should have intended coloring:

\[\033[1;32m\]\u:\[\033[1;34m\] \W \$\[\033[0m\]
                               |_____|
                                  |
                                  +---- Bold blue.

Keeping the "original" this should also work:

\[\033[1;32m\]\u:\[\033[1;34m\] \W\[\033[1;34m\] \$\[\033[0m\]
                                  |_|         |_|
                                   |           |
                                   +-----------+-- Enclose in \[ \]

---

Edit:

The reason for the behavior is because bash believes the prompt is longer then it actually is. As a simple example, if one use:

PS1="\033[0;34m$"
       1 2345678

The prompt is believed to be 8 characters and not 1. As such if terminal window is 20 columns, after typing 12 characters, it is believed to be 20 and wraps around. This is also evident if one then try to do backspace or Ctrl+u. It stops at column 9.

However it also does not start new line unless one are on last column, as a result the first line is overwritten.

If one keep typing the line should wrap to next line after 32 characters.

Answer 2

It is mostly to do with the size of the window assumed by the terminal is not the same as your actual window size. If you are using bash, you can try this.

$ shopt checkwinsize

If you don't get

checkwinsize    on

Then activate it with

$ shopt -s checkwinsize

Then just attempt running another command (like ls) or resizing the window once, the above works for me every time.

For Redhat systems particularly, the issue is often caused by misconfiguring ~/.bashrc not to call /etc/bashrc. Normally, bash loads ~/.bashrc which is expected to call /etc/bashrc, which by default contains shopt -s checkwinsize.

Answer 3

I once read somewhere (don't know where anymore) that using \001 and \002 instead of \[ and \] can solve this issue. It did for me.

By the way, defining PS1 does not have to look ugly.

green="\001$(tput setaf 2)\002"
blue="\001$(tput setaf 4)\002"
dim="\001$(tput dim)\002"
reset="\001$(tput sgr0)\002"

PS1="$dim[\t] " # [hh:mm:ss]
PS1+="$green\u@\h" # user@host
PS1+="$blue\w\$$reset " # workingdir$

export PS1
unset green blue dim reset

Answer 4

As mentioned in other answers, non-printable sequences such as \e[0;30m should be wrapped with \[...\].

Additionally (and what I don't see mentioned yet) is it seems that \r\n should be outside of the \[...\] if you have a multi-line prompt. It took me some of trial and error to finally figure that out.

Answer 5

This sounds like an issue with your COLUMNS & LINES environment variable settings. When you resize the window they're typically set automatically by gnome-terminal (I believe) you can force them to be manually set by issuing the command resize.

Example

If I resize my gnome-terminal to 79x17 my variables show up like so:

$ echo $COLUMNS; echo $LINES
79
17

I can force it like so:

$ resize
COLUMNS=79;
LINES=17;
export COLUMNS LINES;

Answer 6

To prevent wrapping, you can also increase the number of columns using, e.g.

stty columns 120

Answer 7

Also the same issue can be caused by using wide unicode symbols (like from https://stackoverflow.com/a/34812608/1657819). Here is the snippet causing the problem (mind the $Green and $Red are properly escaped color strings):

FancyX='\342\234\227'
Checkmark='\342\234\223'


# Add a bright white exit status for the last command
PS1="$White\$? "
# If it was successful, print a green check mark. Otherwise, print
# a red X.
if [[ $Last_Command == 0 ]]; then
    PS1+="$Green$Checkmark "
else
    PS1+="$Red$FancyX "
fi

Bash cannot calculate the length correctly, so easiest way could be to escape 2 out of three parts of those wide symbols.

FancyX='\[\342\234\]\227'
Checkmark='\[\342\234\]\223'

Answer 8

tput smam

On Ubuntu 19.10 in a Gnome terminal, which has TERM=xterm-256color, this emits the exact escape sequence that makes the terminal wrap lines:

tput smam

You can see what that escape is with:

tput smam | hd

Resetting the terminal state with:

reset

also seems to have the effect of setting tput smam.

The man page:

man terminfo

documents smam and its opposite rmam:

       enter_am_mode   smam   SA   turn on automatic margins
       exit_am_mode    rmam   RA   turn off automatic margins

Note however that certain terminals don't have that capability, e.g. inside tmux we have TERM=screen-265color and smam does not appear on the list of capabilities:

infocmp

and so tput smam doesn't print anything.

I'm not sure how, but QEMU was able to change the line wrap state of tmux while tput wasn't.

Answer 9

I have 2 almost identical Archlinux setups and after I switched one to "powerline" PS1 with Unicode characters I've got the same problem. It turned out that on affected laptop I was missing /etc/locale.conf file

LANG=en_US.UTF-8
LANGUAGE=en_US.UTF-8
LC_COLLATE=en_US.UTF-8

once I've copied it over, terminal became Unicode-aware and "line overlap" problem went away.

Answer 10

Thanks to this article, I've got my prompt working very nicely. And when combined with gitprompt (https://github.com/git/git/blob/master/contrib/completion/git-prompt.sh), I get the exact things I want.

PS1_RESET='\001$(tput sgr0)\002'
PS1_ERROR='$(code=${?##0};echo ${code:+\001$(tput setaf 1)\002[${code}]\ })'"$PS1_RESET"
PS1_SHLVL='\001$(tput setaf 4)\002($SHLVL) '"$PS1_RESET"
PS1_DATE='\001$(tput setaf 5)\002\D{%Y-%m-%d %H:%M:%S} '"$PS1_RESET"
PS1_USER='\001$(tput setaf 6)\002\u'"$PS1_RESET"
PS1_AT='\001$(tput sgr0)\002@'"$PS1_RESET"
PS1_HOST='\001$(tput setaf 2)\002\h'"$PS1_RESET"
PS1_COLON='\001$(tput sgr0)\002:'"$PS1_RESET"
PS1_PATH='\001$(tput setaf 3)\002\w'"$PS1_RESET"
PS1_GIT='$(__git_ps1 " (%s)")'"$PS1_RESET"
PS1_PROMPT=' \\$ '
PS1_COMBINED=$PS1_ERROR$PS1_SHLVL$PS1_DATE$PS1_USER$PS1_AT$PS1_HOST$PS1_COLON$PS1_PATH
export PS1="$PS1_COMBINED"

GIT_PS1_COMPRESSSPARSESTATE=
GIT_PS1_DESCRIBE_STYLE=
GIT_PS1_HIDE_IF_PWD_IGNORED=yes
GIT_PS1_OMITSPARSESTATE=
GIT_PS1_SHOWCOLORHINTS=yes
GIT_PS1_SHOWDIRTYSTATE=yes
GIT_PS1_SHOWSTASHSTATE=yes
GIT_PS1_SHOWUNTRACKEDFILES=yes
GIT_PS1_SHOWUPSTREAM="auto"
GIT_PS1_STATESEPARATOR=" "
export PROMPT_COMMAND='__git_ps1 "$PS1_COMBINED" "$PS1_PROMPT"'

Answer 11

The question asked is for the Bash shell interpreter, as like many of the other questions on similar topic. None, if not few, point to on how to do it on the Zsh shell interpreter.

\[ ... \] or \001 ... \002 won't work with .zshrc. For Zsh, the special characters are %{ and %}. For example, here is how you would configure your prompt with colors in .zshrc :

promptText="megh$ "
PS1="%{$(tput bold)$(tput setaf 3)%}$promptText%{$(tput sgr0)%}"

Link to documentation