介紹
我經常會使用我的電腦看全螢幕的影片，並且需要在等下工作時間到時準時回到工作狀態 —— 但尷尬的是我並不喜歡隨時拿起手機查看當前的時間，因為那樣做很麻煩。
我曾經使用 watch -n 1 date 指令在另外一個螢幕實時地顯示當前時間，讓我可以隨時往一旁查看時間；但是這種顯示方法其實並不美觀，並且字體十分狹小。
最後，我還是找到了個在終端機顯示時鐘的小工具：tty-clock。這也是目前為止我使用得最滿意的。
安裝
sudo apt install tty-clock
直接使用 tty-clock 指令就能在終端機上顯示時間。並且還有幾個常規操作，比方說加上 -s 參數增加秒數、進入之後按 C 可以將時鐘置中、可以使用數字鍵 [0-7] 更換顏色… 等等。
使用方式
指令 Commands
tty-clock accepts a number of runtime keyboard commands, upper and lower case characters
are treated identically.
K,J,H,L
vi-style movement commands to set the position of the displayed clock. These
commands have no effect when the centered option is set.
[0-7] Select a different color for displaying the clock.
B Toggles bewteen bold and normal colors.
X Toggles displaying a box around the clock. This option is disabled by default.
C Toggle the clock's position to centered. When set the movement commands are
disabled.
R Set the clock to rebound along the edges of the terminal.
S Display seconds.
T Switch time output to the 12-hour format.
Q Quit.
參數 Options
-s Show seconds.
-S Screensaver mode. tty-clock terminates when any key is pressed.
-x Show box.
-c Set the clock at the center of the terminal.
-C [0-7]
Set the clock color.
-b Use bold colors.
-t Set the hour in 12h format.
-u Use UTC time.
-T tty Display the clock on the given tty. tty must be a valid character device to which
the user has rw access permissions. (See EXAMPLES)
-r Do rebound the clock.
-f format
Set the date format as described in strftime(3).
-n Do not quit the program when the Q key is pressed (or when any key is pressed while
in Screensaver mode). A signal must be sent to tty-clock in order to terminate its
execution. (See EXAMPLES)
-v Show tty-clock version.
-i Show some info about tty-clock.
-h Show usage information.
-D Hide the date.
-B Enable blinking colon.
-d delay
Set the delay (in seconds) between two redraws of the clock. Default 1s.
-a nsdelay
Additional delay (in nanoseconds) between two redraws of the clock. Default 0ns.