starred/terminal
1
0
Fork 0
mirror of https://github.com/microsoft/terminal.git synced 2026-02-03 21:25:34 +00:00
Code Issues 19.0k Packages Projects Releases 20 Wiki Activity

Strange behaviour of Delete Line and Insert Line when used above the top margin #203

New Issue
Open
opened 2026-01-30 21:45:25 +00:00 by claunia · 0 comments
claunia commented 2026-01-30 21:45:25 +00:00
Owner
Copy Link

Originally created by @j4james on GitHub (Mar 28, 2018).

Originally assigned to: @zadjii-msft on GitHub.

  • Your Windows build number:

Microsoft Windows [Version 10.0.16299.309]

  • What you're doing and what's happening:

I was curious to see how the Delete Line (\033[M) and Insert Line (\033[L) escape sequences would behave when applied above the top margin of the scrolling region. So as a test, I labelled the first 8 lines of the screen with the numbers 1 to 8, set the top margin to line 4, then attempted to delete line 1.

This was the command I used:

printf "\033c1\n2\n3\n4\n5\n6\n7\n8\033[4r\033[H\033[M\033[r" && read -n 1

And this was the output I saw:

1
2
3
8

Instead of 1 row being deleted from line 1, I got 4 rows deleted from line 4.

I then tried the same thing with the Insert Line sequence:

printf "\033c1\n2\n3\n4\n5\n6\n7\n8\033[4r\033[H\033[L\033[r" && read -n 1

And the output this time was:

1
2
3
6
7
8

Instead of 1 row being inserted at line 1, I got 2 rows deleted from line 4!

  • What's wrong / what should be happening instead:

I don't think there is necessarily a "correct" behaviour in this situation, but I do think the current Windows behaviour is probably a bug.

One possible option would be to ignore these commands when used outside the defined margins (which I think is what XTerm does). Another option would be to handle the insert and delete as if the top margin had not been set, but still constrain the scrolling region within the bottom margin (which is how the Linux console behaves). Either choice would be preferable to the current behaviour.

Originally created by @j4james on GitHub (Mar 28, 2018). Originally assigned to: @zadjii-msft on GitHub. * Your Windows build number: Microsoft Windows [Version 10.0.16299.309] * What you're doing and what's happening: I was curious to see how the _Delete Line_ (`\033[M`) and _Insert Line_ (`\033[L`) escape sequences would behave when applied above the top margin of the scrolling region. So as a test, I labelled the first 8 lines of the screen with the numbers 1 to 8, set the top margin to line 4, then attempted to delete line 1. This was the command I used: printf "\033c1\n2\n3\n4\n5\n6\n7\n8\033[4r\033[H\033[M\033[r" && read -n 1 And this was the output I saw: 1 2 3 8 Instead of 1 row being deleted from line 1, I got 4 rows deleted from line 4. I then tried the same thing with the _Insert Line_ sequence: printf "\033c1\n2\n3\n4\n5\n6\n7\n8\033[4r\033[H\033[L\033[r" && read -n 1 And the output this time was: 1 2 3 6 7 8 Instead of 1 row being inserted at line 1, I got 2 rows **deleted** from line 4! * What's wrong / what should be happening instead: I don't think there is necessarily a "correct" behaviour in this situation, but I do think the current Windows behaviour is probably a bug. One possible option would be to ignore these commands when used outside the defined margins (which I think is what XTerm does). Another option would be to handle the insert and delete as if the top margin had not been set, but still constrain the scrolling region within the bottom margin (which is how the Linux console behaves). Either choice would be preferable to the current behaviour.
Sign in to join this conversation.
No Branch/Tag Specified
Branches Tags
Labels
Clear labels
⛺ Reserved
A11yCO
A11yMAS
A11ySev1
A11ySev2
A11ySev3
A11yTTValidated
A11yUsable
A11yVoiceAccess
A11yWCAG
Area-Accessibility
Area-AtlasEngine
Area-AzureShell
Area-Build
Area-Build
Area-Chat
Area-CmdPal
Area-CodeHealth
Area-Commandline
Area-CookedRead
Area-DefApp
Area-Extensibility
Area-Fonts
Area-GroupPolicy
Area-i18n
Area-Input
Area-Interaction
Area-Interop
Area-Localization
Area-Output
Area-Performance
Area-Portable
Area-Quality
Area-Remoting
Area-Rendering
Area-Schema
Area-Server
Area-Settings
Area-SettingsUI
Area-ShellExtension
Area-ShellExtension
Area-ShellExtension
Area-Suggestions
Area-Suggestions
Area-TerminalConnection
Area-TerminalControl
Area-Theming
Area-UserInterface
Area-VT
Area-Windowing
Area-WPFControl
AutoMerge
Blocking-Ingestion
Culprit-Centennial
Culprit-WinUI
Disability-All
Disability-Blind
Disability-LowVision
Disability-Mobility
External-Blocked-WinUI3
Fixed
Gathering-Data
good first issue
HCL-E+D
HCL-WindowsTerminal
Help Wanted
Impact-Compatibility
Impact-Compliance
Impact-Correctness
Impact-Visual
In-PR
InclusionBacklog
InclusionBacklog-Windows TerminalWin32
InclusionCommitted-202206
Issue-Bug
Issue-Docs
Issue-Feature
Issue-Feature
Issue-Question
Issue-Samples
Issue-Scenario
Issue-Task
Needs-Attention
Needs-Author-Feedback
Needs-Bisect
Needs-Discussion
Needs-Repro
Needs-Tag-Fix
Needs-Tag-Fix
Needs-Triage
No-Recent-Activity
Priority-0
Priority-1
Priority-2
Priority-3
Product-Cmd.exe
Product-Colortool
Product-Colortool
Product-Colortool
Product-Conhost
Product-Conpty
Product-Meta
Product-Powershell
Product-Terminal
Product-WSL
pull-request
Mirrored from GitHub Pull Request
 Resolution-Answered
Resolution-By-Design
Resolution-Duplicate
Resolution-External
Resolution-Fix-Available
Resolution-Fix-Committed
Resolution-No-Repro
Resolution-Won't-Fix
Severity-Blocking
Severity-Crash
Severity-DataLoss
spam
this-will-be-a-breaking-change
Tracking-External
WindowsTerminal_Win32
Work-Item
zAskModeBug
zInbox-Bug
No Label Area-VT Issue-Bug Product-Conhost Resolution-Fix-Available Work-Item
Milestone
No items
No Milestone
Projects
Clear projects
No project
Assignees
Clear assignees
claunia
No Assignees
1 Participants
Notifications
Due Date
No due date set.
Dependencies

No dependencies set.

Reference: starred/terminal#203
Delete Branch "%!s()"

Deleting a branch is permanent. Although the deleted branch may continue to exist for a short time before it actually gets removed, it CANNOT be undone in most cases. Continue?