tui-cs/Terminal.Gui · error · NotSupportedException

"{_xclipPath} {xclipArgs} < {text}" failed

Error message

"{_xclipPath} {xclipArgs} < {text}" failed

What it means

Thrown by UnixClipboard.SetClipboardDataImpl when invoking xclip to write to the clipboard selection raises an exception, wrapping the original. It is a NotSupportedException. Note the message interpolates the text being set, which can leak clipboard contents into logs; xclip was found at construction (IsSupported true) but the write failed at runtime.

Source

Thrown at Terminal.Gui/Drivers/UnixHelpers/UnixClipboard.cs:59

        finally
        {
            File.Delete (tempFileName);
        }

        return string.Empty;
    }

    protected override void SetClipboardDataImpl (string text)
    {
        string xclipArgs = "-selection clipboard -i";

        try
        {
            _processRunner.Bash ($"{_xclipPath} {xclipArgs}", text);
        }
        catch (Exception e)
        {
            throw new NotSupportedException ($"\"{_xclipPath} {xclipArgs} < {text}\" failed", e);
        }
    }

    private bool CheckSupport ()
    {
#pragma warning disable RCS1075 // Avoid empty catch clause that catches System.Exception.
        try
        {
            (int exitCode, string result) = _processRunner.Bash ("which xclip", waitForOutput: true);

            if (exitCode == 0 && result.FileExists ())
            {
                _xclipPath = result;

                return true;
            }
        }
        catch (Exception)

View on GitHub (pinned to 2e47b11478)

Solutions

1. Check Clipboard.IsSupported before calling SetText and skip silently if unsupported.
2. Ensure a usable X session (DISPLAY set, ssh -X, or XWayland).
3. Verify manually: `echo test | xclip -selection clipboard -i`.

Example fix

// before
Clipboard.SetText(value);

// after
if (Clipboard.IsSupported)
    Clipboard.SetText(value);

if (!Clipboard.IsSupported) return;

static bool ClipboardReady() => Clipboard.IsSupported;

try { Clipboard.SetText(value); } catch (NotSupportedException) { /* ignore; clipboard unavailable */ }

When it happens

Trigger: Calling Clipboard.SetText (or SetClipboardDataImpl) on Linux when xclip is installed but the write fails: no X display, not in an X/Wayland session, permission denied, or xclip killed mid-write.

Common situations: SSH sessions without X forwarding, headless/CI boxes, Wayland without XWayland, or environments where xclip cannot reach a clipboard daemon.

Related errors

• "{_xclipPath} {xclipArgs}" failed.
• Failed to copy from the OS clipboard.
• Failed to paste to the OS clipboard.
• Process timed out. Command line: {process.StartInfo.FileName
• Failed to get screenBuffer console mode, error code: {Marsha

AI-assisted analysis of tui-cs/Terminal.Gui@2e47b11478 (2026-08-13). Data as JSON: /api/errors/21e12a31ba0f1044. Report an issue: GitHub.