repository·main·Indexed 13 days ago
https://github.com/microsoft/terminalSource code and documentation for Windows Terminal, Windows Terminal Preview, and the Windows Console Host (conhost.exe). Includes the base/numerics C++ library for safe numeric operations using CheckedNumeric, ClampedNumeric, and StrictNumeric templates to handle overflow, underflow, and type conversions.
The base/numerics library is a dependency-free, header-only C++ library providing templates for safe and performant numeric operations and conversions. It is organized into several key headers:
checked_math.h: Provides CheckedNumeric for arithmetic and conversions that detect errors like overflow or truncation.clamped_math.h: Provides ClampedNumeric for fast, non-sticky saturating (clamped) arithmetic.safe_conversions.h: Provides StrictNumeric and various casting templates for safe type conversion.safe_math.h: A convenience header that includes all the above.Type Coercion Priority: When using these numeric types, they implicitly convert according to this priority:
StrictNumeric coerces to ClampedNumeric and CheckedNumeric.ClampedNumeric coerces to CheckedNumeric.The Settings UI is organized into a hierarchical navigation structure accessible via a left-hand navigation bar. The top-level categories and their sub-items are:
The Terminal 2.0 roadmap outlines key functional scenarios categorized by priority. These scenarios define the evolution of the terminal's user experience, ranging from mandatory core features to optional stretch goals.
settings.json.The Windows Terminal accessibility roadmap prioritizes work items based on their impact on the command-line ecosystem. The priorities are categorized into three buckets:
Key work items include VT Screen Reader Control, Shell suggestions, Search improvements, and Mark Mode support for degenerate ranges (Priority 1), as well as respecting High Contrast Mode and Text Size OS settings (Priority 2).
The Suggestions UI is an ephemeral, Intellisense-like interface within Windows Terminal that appears at the point of text insertion. It provides actionable UI elements to the user based on context, helping to provide immediate content suggestions directly within the terminal control.
Key capabilities include:
sendInput actions in user settings).This repository contains two primary command-line experiences:
conhost.exe): The original Windows command-line experience. It hosts the Windows Console API server, input/rendering engines, and user preferences. While it maintains backward compatibility, it lacks modern features like tabs and advanced Unicode support found in Windows Terminal.Shared Components: The repository also contains modernized components (like a DirectWrite-based text engine and a VT parser) that are shared between the Console and the Terminal.
The ITerminalConnection interface uses a state machine to track the lifecycle of a connection. Implementations must treat states as a directed acyclic graph (DAG) and must not transition in reverse.
Connection States (TerminalConnection::ConnectionState):
NotConnected: The initial state for all new connections.Connecting: The connection process has started but is not yet active.Connected: The connection is active and ready.Closing: The connection is being closed (typically via user request).Closed: The connection terminated successfully (normal exit).Failed: The connection was unexpectedly terminated (e.g., process crash or failed to spawn).Events:
StateChanged(ITerminalConnection, IInspectable): This event is triggered whenever the connection transitions between states. It replaces the deprecated TerminalDisconnected event.To support features like tab tearoff and improved reliability, the design proposes moving away from a single-process model to a multi-mode architecture where wt.exe can run in different functional roles:
wt.exe - Manager Mode
|- wt.exe - Frame Host Mode
| |- wt.exe - Tab Host Mode
| | |- conhost.exe - ConPTY mode
| | |- pwsh.exe - Client application
| |- wt.exe - Tab Host Mode
| |- conhost.exe - ConPTY mode
| |- cmd.exe - Client application
|- wt.exe - Frame Host Mode
|- wt.exe - Tab Host Mode
|- conhost.exe - ConPTY mode
|- pwsh.exe - Client applicationAnother proposal involves adding a special profile object to the profiles array with the magic GUID "__default__". Any settings defined in this specific profile object are applied to all other profiles in the list.
{
"profiles":
[
{
"guid": "__default__",
"useAcrylic": true,
"acrylicOpacity": 0.1,
"fontFace": "Cascadia Code",
"fontSize": 10
},
{
"guid": "{61c54bbd-c2c6-5271-96e7-009a87ff44bf}",
"name": "Windows PowerShell",
"commandline": "powershell.exe"
}
]
}This design describes how Windows Terminal handles being launched as the default application for console client applications (via conhost.exe) to ensure a seamless user experience.
When conhost.exe is triggered by the system to host a client application, it locates the installed wt.exe package and launches it with specific parameters to use the client's connection as its first tab (instead of the default startup tab). In this mode, conhost.exe remains invisible, operating in ConPTY mode, so only the new wt.exe window is visible to the user.
If a wt.exe instance is already active, conhost.exe identifies the running instance and adds the new client application as a new tab at the end of the existing tab bar.
If multiple instances exist, the system must determine which instance should receive the new tab (e.g., the foreground instance, the active instance, or a designated primary/manager instance).