Fix freeze on copy when xclip is installed on Linux

[louisbourque]

This Pull Request fixes/closes #1497

It changes the following:

• It adds a boolean argument to determine if stderr should be piped, and sets it to false when running the xclip command.

I was able to reproduce the linked issue. If I run killall xclip then the UI resumes normal function. This issue started with e371153. Removing the .stderr(Stdio::piped()) line fixes the freezing, but breaks the error reporting.

xclip waits for input on stdin. Something about piping stderr and stdin seems to cause the program to continue waiting for input. I tried different arguments to pass to xclip to tell it to exit, but nothing I tried seemed to work. I tried writing \x03 (End of Text) and \x04 (End of Transmission) and a few others that may have indicated to xclip to close. I tried passing -l 1 (loop once then exit) which fixes the freezing, but results in the wrong thing being set on the clipboard. (It would always set the previous thing I copied, instead of the last)

In the end, passing a boolean to the function to indicate whether or not stderr should be piped seems to do the trick. If the command fails, we retry with xsel anyway, and report the error from that command. So the stderr output from xclip isn't needed.

I followed the checklist:

• I added unittests
• I ran make check without errors
• I tested the overall application
• I added an appropriate item to the changelog

[senekor]

Hello! Thanks for opening this. I'm having the exact same problem with wl-copy and your fix works with that as well:

if std::env::var("WAYLAND_DISPLAY").is_ok() {
	return exec_copy_with_args("wl-copy", &[], text, false);
}

[extrawurst]

Thanks guys ❤️