linux - 试图运行 xdotool 但得到 'Can' t open display : (null)'

Question

我很抱歉再次报告这个众所周知的错误消息。
没有什么对我有用。我在 MacOS Catalina 上运行，如果它很重要的话。
我安装了 xdotool与 brew在我的 Mac 上尝试运行

xdotool getmouselocation

下面的错误信息是

Error: Can't open display: (null)
Failed creating new xdo instance

我一直在寻找解决方案，找到了很多答案。运行 export DISPLAY=:0一切都很好。但这对我不起作用。
PS:为了更好地理解:DISPLAY 到底是什么意思？是我电脑的显示器吗？

Answer 1

根据 official notice by apple

X11 is no longer included with Mac, but X11 server and client libraries are available from the XQuartz project.

为什么 X11 在这种情况下很重要？
xdotool - 命令行 X11 自动化工具。
所以除了设置 export DISPLAY=:0安装 xquartz .
DISPLAY 究竟是什么意思？
根据 x manual

From the user's perspective, every X server has a display name of the form:

               hostname:displaynumber.screennumber

This information is used by the application to determine how it shouldconnect to the server and which screen it should use by default (ondisplays with multiple monitors):

1. hostnameThe hostname specifies the name of the machine to which the display is physically connected. If the hostname is not given, themost efficient way of communicating to a server on the same machinewill be used.

2. displaynumberThe phrase "display" is usually used to refer to collection of monitors that share a common keyboard and pointer (mouse, tablet,etc.). Most workstations tend to only have one keyboard, andtherefore, only one display. Larger, multi-user systems, however,frequently have several displays so that more than one person can bedoing graphics work at once. To avoid confusion, each display on amachine is assigned a display number (beginning at 0) when the Xserver for that display is started. The display number must always begiven in a display name.

3. screennumberSome displays share a single keyboard and pointer among two or more monitors. Since each monitor has its own set of windows, eachscreen is assigned a screen number (beginning at 0) when the X serverfor that display is started. If the screen number is not given, screen0 will be used.

找到了更简单的描述 here
显示包括(简化):

一个键盘

一只老鼠

一屏

即当您通过 ssh 连接时，您使用的是这 3 个的不同集合。