iOS模拟器运行时出现Pseudo Terminal Setup Error问题及修复咨询

Hey there, let's break down this error and get your app running in the iOS Simulator again. That Errno 6 corresponds to ENXIO—a system error meaning "No such device or address"—and it pops up when the Simulator fails to set up the pseudo terminal (pty) it uses to communicate with your app. This is almost always tied to temporary state issues, permission problems, or cached data. Here are the steps to fix it:

• Fully restart Xcode and the Simulator
  First, quit Xcode completely (press Cmd + Q), then open the Simulator and use the menu bar to select Simulator > Quit Simulator (don't just close the window). Wait a few seconds, then launch both apps again. Temporary glitches in their runtime state often cause this error, and a fresh start clears it up.

• Reset Simulator Content & Settings
  In the Simulator, go to Device > Erase All Content and Settings. Confirm the action when prompted, and let the Simulator reset. This wipes out cached app data, preferences, and any corrupted terminal configurations that might be blocking the setup.

• Verify Xcode's System Permissions
  Sometimes Xcode lacks the necessary access to system terminal devices. Head to System Settings > Privacy & Security > Full Disk Access, make sure Xcode is listed there and its toggle is enabled. If it's already on, toggle it off, wait 10 seconds, then toggle it back on. Restart Xcode after this change.

• Reboot your Mac
  It sounds basic, but system-level device nodes for pseudo terminals can get stuck in a broken state. A full reboot resets these system resources, often resolving the underlying issue that's causing the pty setup to fail.

• Reinstall Xcode Command Line Tools
  Open Terminal and run xcode-select --install to trigger a fresh install of the command line tools. If they're already installed, first reset the path with sudo xcode-select --reset, then run the install command again. These tools handle low-level terminal interactions that the Simulator relies on.

• Disable third-party terminal/ system tools temporarily
  If you use tools like iTerm2 with custom plugins, tmux, or system optimization utilities, they might be modifying the terminal environment in a way that conflicts with the Simulator. Disable these tools temporarily, then try launching the Simulator again to see if the error goes away.

If none of the above steps work, a last resort is to uninstall and reinstall Xcode—but this should only be necessary if all other fixes fail.

内容的提问来源于stack exchange，提问作者user3151675