通过终端在远程服务器上执行长时间运行的任务时，因为突然的断开导致 SSH 会话终止，使得程序运行失败！使用 screen 能够避免上面情况的发生。同时，让我们在一个终端上可以运行多个终端程序，并可以自由切换这些终端。

Screen 或 GNU Screen 是一个终端多路复用器。换句话说，这意味着您可以启动一个屏幕会话，然后在该会话中打开任意数量的窗口（虚拟终端）。在 Screen 中运行的进程在它们的窗口不可见时将继续运行，即使您断开连接也是如此。

安装 screen

Debian or Ubuntu 操作系统安装方法如下：

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sudo apt update
sudo apt install screen -y

RedHat or CentOS or Fedora 操作系统安装方法如下：

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sudo yum install screen

使用 screen

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# 创建一个名字为 main 的 screen 终端
screen -S main

# 查看打开了哪些 screen 终端
screen -ls

# 退出名字为 main 的 screen 终端，也可以不用名字，采用 screen -ls 罗列的 screen 进程 id
screen -d main
# 如果终端上正在运行程序，可以采用快捷键 "ctrl + a, d" 退出终端

# 强制分离打开main的screen并转移到当前窗口
screen -d -r main 

# 重新进入名字为 main 的 screen 终端
screen -r main

# 共享会话。可以远程和朋友共享同一个会话，一方输入的命令事实在另一方可看
# 首先一方打开一个会话，如 main，然后，另一方输入如下命令
screen -x main

# 清理死掉的 screen
screen -wipe

# 退出或杀死 screen，使用 screen -ls 查看想要关闭的 screen id
screen -S screen_id -X quit
screen -S main -X quit  # 或者使用 screen 名
# 或者进入 screen 后，正常退出终端
exit
ctrl + d

# 查看当前终端是哪个 screen
echo $STY

# 默认无法进行鼠标滚轮翻页，但可以复制和拷贝。如果想要翻页，可以进入翻页模式，快捷键是
ctrl + a, [
ctrl + a, esc
# 退出翻页模式，进入正常模式（可拷贝）
ctrl + c
esc

以下是一些用于管理 Linux Screen 窗口的最常用快捷键：

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ctrl+a d      分离当前screen
ctrl+a k      关闭并杀死当前screen
Ctrl+a c      Create a new window (with shell).
Ctrl+a "      List all windows.
Ctrl+a 0      Switch to window 0 (by number).
Ctrl+a A      Rename the current window.
Ctrl+a S      Split current region horizontally into two regions.
Ctrl+a |      Split current region vertically into two regions.
Ctrl+a tab    Switch the input focus to the next region.
Ctrl+a Ctrl+a Toggle between the current and previous windows
Ctrl+a Q      Close all regions but the current one.
Ctrl+a X      Close the current region.

配置文件

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vim ~/.screenrc

添加如下内容

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# $Id: screenrc,v 1.15 2003/10/08 11:39:03 zal Exp $
#
# /etc/screenrc
#
#   This is the system wide screenrc.
#
#   You can use this file to change the default behavior of screen system wide
#   or copy it to ~/.screenrc and use it as a starting point for your own
#   settings.
#
#   Commands in this file are used to set options, bind screen functions to
#   keys, redefine terminal capabilities, and to automatically establish one or
#   more windows at the beginning of your screen session.
#
#   This is not a comprehensive list of options, look at the screen manual for
#   details on everything that you can put in this file.
#

# ------------------------------------------------------------------------------
# SCREEN SETTINGS
# ------------------------------------------------------------------------------

#startup_message off
#nethack on

#defflow on # will force screen to process ^S/^Q
deflogin on
#autodetach off

# turn visual bell on
vbell on
vbell_msg "   Wuff  ----  Wuff!!  "

# define a bigger scrollback, default is 100 lines
# 鼠标翻页的行数，默认1024，可根据自己需要调整
defscrollback 10240000

# ------------------------------------------------------------------------------
# SCREEN KEYBINDINGS
# ------------------------------------------------------------------------------

# Remove some stupid / dangerous key bindings
bind ^k
#bind L
bind ^\
# Make them better
bind \\ quit
bind K kill
bind I login on
bind O login off
bind } history

# An example of a "screen scraper" which will launch urlview on the current
# screen window
#
#bind ^B eval "hardcopy_append off" "hardcopy -h $HOME/.screen-urlview" "screen urlview $HOME/.screen-urlview"

# ------------------------------------------------------------------------------
# TERMINAL SETTINGS
# ------------------------------------------------------------------------------

# The vt100 description does not mention "dl". *sigh*
termcapinfo vt100 dl=5\E[M

# turn sending of screen messages to hardstatus off
hardstatus off
# Set the hardstatus prop on gui terms to set the titlebar/icon title
termcapinfo xterm*|rxvt*|kterm*|Eterm* hs:ts=\E]0;:fs=\007:ds=\E]0;\007
# use this for the hard status string
hardstatus string "%h%? users: %u%?"

# An alternative hardstatus to display a bar at the bottom listing the
# windownames and highlighting the current windowname in blue. (This is only
# enabled if there is no hardstatus setting for your terminal)
#
#hardstatus lastline "%-Lw%{= BW}%50>%n%f* %t%{-}%+Lw%<"

# set these terminals up to be 'optimal' instead of vt100
termcapinfo xterm*|linux*|rxvt*|Eterm* OP

# Change the xterm initialization string from is2=\E[!p\E[?3;4l\E[4l\E>
# (This fixes the "Aborted because of window size change" konsole symptoms found
#  in bug #134198)
termcapinfo xterm 'is=\E[r\E[m\E[2J\E[H\E[?7h\E[?1;4;6l'

# To get screen to add lines to xterm's scrollback buffer, uncomment the
# following termcapinfo line which tells xterm to use the normal screen buffer
# (which has scrollback), not the alternate screen buffer.
#
#termcapinfo xterm|xterms|xs|rxvt ti@:te@

# Enable non-blocking mode to better cope with flaky ssh connections.
defnonblock 5

# ------------------------------------------------------------------------------
# STARTUP SCREENS
# ------------------------------------------------------------------------------

# Example of automatically running some programs in windows on screen startup.
#
#   The following will open top in the first window, an ssh session to monkey
#   in the next window, and then open mutt and tail in windows 8 and 9
#   respectively.
#
# screen top
# screen -t monkey ssh monkey
# screen -t mail 8 mutt
# screen -t daemon 9 tail -f /var/log/daemon.log


#hardstatus alwayslastline "%-Lw%50>%n%f* %t%+Lw%<"
hardstatus alwayslastline
shelltitle "$|bash"

hardstatus string '%{= kG}[ %Y/%m/%d %{G}%c:%s %{g}][%= %{= kw}%?%-Lw%?%{Y}%n*%f%t %{K}%?%+Lw%?%= %{kG}][ %{C}Author@Jinzhong Xu%{kg}]'
#hardstatus string '%{= kG}[ %Y/%m/%d %{G}%c:%s %{g}][%= %{= kw}%?%-Lw%?%{Y}%n*%f%t %{K}%?%+Lw%?%= %{kG}][ %{C}(F8)Screen (F9)Title (F10)Detach (F11)Prev (F12)Next %{kg}]'
#hardstatus string '%{= kG}[ %{G}%c:%s %{g}][%= %{= kw}%?%-Lw%?%{Y}%n*%f%t %{K}%?%+Lw%?%= %{kG}][ %{C}(F8)Screen (F9)Title (F10)Detach (F11)Prev (F12)Next %{kg}][%{kG} %l %Y/%m/%d %{kG}]'

# a short version, can use C-a
#hardstatus string '%{= kg}[ %{G}%c:%s %{g}][%= %{= kw}%?%-Lw%?%{Y}%n*%f%t %{K}%?%+Lw%?%= %{g}][%{kG} %D %Y/%m/%d %{g}]'

# Set default encoding using utf8
defutf8 on

## 解决中文乱码,这个要按需配置
defencoding utf8
encoding utf8 utf8

参考文献

  1. How To Use Linux Screen
  2. screen command in Linux with Examples
  3. Linux命令screen—终端切换，工作环境保存，画面同步，防断网