光标上移 (CUU)

参数 n 必须是大于等于 1 的整数。如果 n 小于 等于 0，则将 n 调整为 1。如果省略 n，则 n 默认为 1。

此序列总是取消待定换行状态。

如果当前光标位置在 上边距 处或之下， 光标能移动到的最高点是上边距。如果当前光标位置在上边距之上， 光标能移动到的最高点是第一行。

printf "\033[1;1H" # move to top-left
printf "\033[0J" # clear screen
printf "\033[3;1H"
printf "A"
printf "\033[2A" # cursor up
printf "X"

|_Xc_______|
|__________|
|A_________|

printf "\033[1;1H" # move to top-left
printf "\033[0J" # clear screen
printf "\n\n\n\n" # screen is 4 high
printf "\033[2;4r" # set scrolling region
printf "\033[3;1H"
printf "A"
printf "\033[5A" # cursor up
printf "X"

|__________|
|_Xc_______|
|A_________|
|__________|

printf "\033[1;1H" # move to top-left
printf "\033[0J" # clear screen
printf "\n\n\n\n\n" # screen is 5 high
printf "\033[3;5r" # set scrolling region
printf "\033[3;1H"
printf "A"
printf "\033[2;1H" # move above region
printf "\033[5A" # cursor up
printf "X"

|Xc________|
|__________|
|A_________|
|__________|
|__________|