WinptyShellBackend class

A ShellBackend that runs interactive shells on a real Windows pseudo-console allocated through libwinpty (winpty.dll, bundled with Git for Windows) via dart:ffi.

It is the Windows counterpart of `ScriptPtyShellBackend`, which is POSIX-only. Like that backend it decorates a fallback (the pipe-based ProcessShellBackend) and delegates to it when:

  • the request carries no PtySpec (e.g. exec mode), or
  • the platform is not Windows, or
  • winpty.dll / a usable Git bash cannot be found, or
  • a spawn fails — after the first such failure the winpty path is disabled for the process and every session uses the pipe fallback.

The winpty CLI is deliberately not used: from pipe-backed stdio it derives geometry via ioctl(STDIN, TIOCGWINSZ), gets 0×0 and asserts before the child starts. Calling the library directly with an explicit initial size avoids it.

Implemented types

Constructors

WinptyShellBackend({required ShellBackend fallback, String? defaultShell, String? workingDirectory, Map<String, String> baseEnvironment = const {}, bool allowCommand(ShellRequest request)?, void onWarning(String message)?})
Creates a winpty-based PTY backend decorating fallback.

Properties

allowCommand → bool Function(ShellRequest request)?
Optional guard; when it returns false the session is refused.
final
baseEnvironment → Map<String, String>
Extra environment overlaid on the inherited environment for every session.
final
defaultShell → String
The interactive shell (bash) winpty wraps; resolved on Windows.
final
fallback → ShellBackend
Backend used for exec sessions and whenever the winpty path is unavailable.
final
hashCode → int
The hash code for this object.
no setterinherited
onWarning → void Function(String message)?
Optional sink for a one-time warning when the winpty path is disabled.
final
runtimeType → Type
A representation of the runtime type of the object.
no setterinherited
workingDirectory → String?
Working directory applied when a request does not specify one.
final

Methods

noSuchMethod(Invocation invocation) → dynamic
Invoked when a nonexistent method or property is accessed.
inherited
start(ShellRequest request) → Future<ShellSession>
Starts a session for request, returning a live ShellSession.
override
toString() → String
A string representation of this object.
inherited

Operators

operator ==(Object other) → bool
The equality operator.
inherited