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[Egmont Koblinger <egmont@xxxxxxxxx>]

This is not a gnome-terminal bug, you'll see the same behavior in every
terminal.

The problem is that there's no reliable way of querying where the cursor
is, so bash assumes it's in the 1st column when it prints the prompt and
edits the command line.  If it's not there, screen corruption is bound
to happen.

I recomment you to accept this and get used to pressing Enter if a
command doesn't terminate with a newline -- or if it's one of your
commands then alter it accordingly.

One trick I've seen is: from the beginning of the prompt (or maybe using
the PROMPT_COMMAND variable) emit a widthful of spaces, followed by a
carriage return (but no newine).  If the cursor was in the 1st column
then it will stay in the same line and this operation will basically
have no effect (well, it will fill up the line with spaces which causes
different behavior when copy-pasting; after the carriage return you
might also output \e[K to remove them).  If the cursor was anywhere else
than in the first column then it overflows to the next line and then
moves back the cursor to the beginning of the next line.  So effectively
this is a "print a newline unless the cursor is in the 1st column".
(I've seen it in a variant where the first character printed is not a
space but an inverse-colored % symbol, giving you an obvious clue that
the final newline was not printed by the app.)

-- 
You received this bug notification because you are a member of Desktop
Packages, which is subscribed to gnome-terminal in Ubuntu.
https://bugs.launchpad.net/bugs/1419339

Title:
  Terminal input offset incorrect after output with no trailing newline
  and  then cycling up through commands

Status in gnome-terminal package in Ubuntu:
  New

Bug description:
  Steps to recreate problem:

  1. Run a very long command, the command should be wider than the
  terminal width so it wraps round to the next line. For this example,
  run a long echo command, such as:

  echo "joi fowiejf fsweiofj woifj weiof weif wioejf weif woifjw ofwioe
  fdwiojf wfw
  fiowejfeiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiijjjjjjjjjjjjjjjjddjj
  fjwepf fweijf fwekfnwe fwef wefw efe fewf wef wef"

  2. Run program that outputs to stdout without a trailing newline, e.g.

  printf "oiwjgoiwgoiwoiawbn"

  So your terminal should look like:
  oiwjgoiwgoiwoiawbnusername@pcname:~$

  3. Use the up arrow key to go back to the long command you entered

  4. Press the home button. The cursor goes to the wrong location,
  behind the start of the actual command and the start of where the
  command would be had it not been for the printf command.

  Then move the cursor to just before the echo statement, and type less
  to change "echo" to "lessecho" (a version of echo which expands meta
  characters). You should notice what the problem is now, the location
  your cursor appears to be at is not the actual location in the
  command, but where it would be if the printf command had not just been
  run.

  
  This is annoying because it can cause you to incorrectly modify old commands.

  ProblemType: Bug
  DistroRelease: Ubuntu 14.04
  Package: gnome-terminal 3.6.2-0ubuntu1
  ProcVersionSignature: Ubuntu 3.13.0-44.73-generic 3.13.11-ckt12
  Uname: Linux 3.13.0-44-generic x86_64
  ApportVersion: 2.14.1-0ubuntu3.6
  Architecture: amd64
  CurrentDesktop: Unity
  Date: Sat Feb  7 20:04:37 2015
  InstallationDate: Installed on 2015-01-18 (20 days ago)
  InstallationMedia: Ubuntu 14.04.1 LTS "Trusty Tahr" - Release amd64 (20140722.2)
  SourcePackage: gnome-terminal
  UpgradeStatus: No upgrade log present (probably fresh install)

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