36.5. “着色” 脚本
ANSI [1] 转义序列设置屏幕属性，例如粗体文本以及前景色和背景色。 DOS 批处理文件 常使用 ANSI 转义码进行颜色输出，Bash 脚本也可以这样做。
示例 36-13. “着色” 地址数据库
#!/bin/bash
# ex30a.sh: "Colorized" version of ex30.sh.
# Crude address database
clear # Clear the screen.
echo -n " "
echo -e '\E[37;44m'"\033[1mContact List\033[0m"
# White on blue background
echo; echo
echo -e "\033[1mChoose one of the following persons:\033[0m"
# Bold
tput sgr0 # Reset attributes.
echo "(Enter only the first letter of name.)"
echo
echo -en '\E[47;34m'"\033[1mE\033[0m" # Blue
tput sgr0 # Reset colors to "normal."
echo "vans, Roland" # "[E]vans, Roland"
echo -en '\E[47;35m'"\033[1mJ\033[0m" # Magenta
tput sgr0
echo "ambalaya, Mildred"
echo -en '\E[47;32m'"\033[1mS\033[0m" # Green
tput sgr0
echo "mith, Julie"
echo -en '\E[47;31m'"\033[1mZ\033[0m" # Red
tput sgr0
echo "ane, Morris"
echo
read person
case "$person" in
# Note variable is quoted.
"E" | "e" )
# Accept upper or lowercase input.
echo
echo "Roland Evans"
echo "4321 Flash Dr."
echo "Hardscrabble, CO 80753"
echo "(303) 734-9874"
echo "(303) 734-9892 fax"
echo "revans@zzy.net"
echo "Business partner & old friend"
;;
"J" | "j" )
echo
echo "Mildred Jambalaya"
echo "249 E. 7th St., Apt. 19"
echo "New York, NY 10009"
echo "(212) 533-2814"
echo "(212) 533-9972 fax"
echo "milliej@loisaida.com"
echo "Girlfriend"
echo "Birthday: Feb. 11"
;;
# Add info for Smith & Zane later.
* )
# Default option.
# Empty input (hitting RETURN) fits here, too.
echo
echo "Not yet in database."
;;
esac
tput sgr0 # Reset colors to "normal."
echo
exit 0 |
示例 36-14. 绘制方框
#!/bin/bash
# Draw-box.sh: Drawing a box using ASCII characters.
# Script by Stefano Palmeri, with minor editing by document author.
# Minor edits suggested by Jim Angstadt.
# Used in the ABS Guide with permission.
######################################################################
### draw_box function doc ###
# The "draw_box" function lets the user
#+ draw a box in a terminal.
#
# Usage: draw_box ROW COLUMN HEIGHT WIDTH [COLOR]
# ROW and COLUMN represent the position
#+ of the upper left angle of the box you're going to draw.
# ROW and COLUMN must be greater than 0
#+ and less than current terminal dimension.
# HEIGHT is the number of rows of the box, and must be > 0.
# HEIGHT + ROW must be <= than current terminal height.
# WIDTH is the number of columns of the box and must be > 0.
# WIDTH + COLUMN must be <= than current terminal width.
#
# E.g.: If your terminal dimension is 20x80,
# draw_box 2 3 10 45 is good
# draw_box 2 3 19 45 has bad HEIGHT value (19+2 > 20)
# draw_box 2 3 18 78 has bad WIDTH value (78+3 > 80)
#
# COLOR is the color of the box frame.
# This is the 5th argument and is optional.
# 0=black 1=red 2=green 3=tan 4=blue 5=purple 6=cyan 7=white.
# If you pass the function bad arguments,
#+ it will just exit with code 65,
#+ and no messages will be printed on stderr.
#
# Clear the terminal before you start to draw a box.
# The clear command is not contained within the function.
# This allows the user to draw multiple boxes, even overlapping ones.
### end of draw_box function doc ###
######################################################################
draw_box(){
#=============#
HORZ="-"
VERT="|"
CORNER_CHAR="+"
MINARGS=4
E_BADARGS=65
#=============#
if [ $# -lt "$MINARGS" ]; then # If args are less than 4, exit.
exit $E_BADARGS
fi
# Looking for non digit chars in arguments.
# Probably it could be done better (exercise for the reader?).
if echo $@ | tr -d [:blank:] | tr -d [:digit:] | grep . &> /dev/null; then
exit $E_BADARGS
fi
BOX_HEIGHT=`expr $3 - 1` # -1 correction needed because angle char "+"
BOX_WIDTH=`expr $4 - 1` #+ is a part of both box height and width.
T_ROWS=`tput lines` # Define current terminal dimension
T_COLS=`tput cols` #+ in rows and columns.
if [ $1 -lt 1 ] || [ $1 -gt $T_ROWS ]; then # Start checking if arguments
exit $E_BADARGS #+ are correct.
fi
if [ $2 -lt 1 ] || [ $2 -gt $T_COLS ]; then
exit $E_BADARGS
fi
if [ `expr $1 + $BOX_HEIGHT + 1` -gt $T_ROWS ]; then
exit $E_BADARGS
fi
if [ `expr $2 + $BOX_WIDTH + 1` -gt $T_COLS ]; then
exit $E_BADARGS
fi
if [ $3 -lt 1 ] || [ $4 -lt 1 ]; then
exit $E_BADARGS
fi # End checking arguments.
plot_char(){ # Function within a function.
echo -e "\E[${1};${2}H"$3
}
echo -ne "\E[3${5}m" # Set box frame color, if defined.
# start drawing the box
count=1 # Draw vertical lines using
for (( r=$1; count<=$BOX_HEIGHT; r++)); do #+ plot_char function.
plot_char $r $2 $VERT
let count=count+1
done
count=1
c=`expr $2 + $BOX_WIDTH`
for (( r=$1; count<=$BOX_HEIGHT; r++)); do
plot_char $r $c $VERT
let count=count+1
done
count=1 # Draw horizontal lines using
for (( c=$2; count<=$BOX_WIDTH; c++)); do #+ plot_char function.
plot_char $1 $c $HORZ
let count=count+1
done
count=1
r=`expr $1 + $BOX_HEIGHT`
for (( c=$2; count<=$BOX_WIDTH; c++)); do
plot_char $r $c $HORZ
let count=count+1
done
plot_char $1 $2 $CORNER_CHAR # Draw box angles.
plot_char $1 `expr $2 + $BOX_WIDTH` $CORNER_CHAR
plot_char `expr $1 + $BOX_HEIGHT` $2 $CORNER_CHAR
plot_char `expr $1 + $BOX_HEIGHT` `expr $2 + $BOX_WIDTH` $CORNER_CHAR
echo -ne "\E[0m" # Restore old colors.
P_ROWS=`expr $T_ROWS - 1` # Put the prompt at bottom of the terminal.
echo -e "\E[${P_ROWS};1H"
}
# Now, let's try drawing a box.
clear # Clear the terminal.
R=2 # Row
C=3 # Column
H=10 # Height
W=45 # Width
col=1 # Color (red)
draw_box $R $C $H $W $col # Draw the box.
exit 0
# Exercise:
# --------
# Add the option of printing text within the drawn box. |
最简单，也许也是最有用的 ANSI 转义序列是粗体文本，\033[1m ... \033[0m。\033 代表 escape（转义），“[1” 开启粗体属性，而 “[0” 关闭它。“m” 终止转义序列的每一项。
bash$ echo -e "\033[1mThis is bold text.\033[0m" |
类似的转义序列开启下划线属性（在 rxvt 和 aterm 中）。
bash$ echo -e "\033[4mThis is underlined text.\033[0m" |
 | 使用 echo，-e选项启用转义序列。 |
其他转义序列更改文本和/或背景颜色。
bash$ echo -e '\E[34;47mThis prints in blue.'; tput sgr0 bash$ echo -e '\E[33;44m'"yellow text on blue background"; tput sgr0 bash$ echo -e '\E[1;33;44m'"BOLD yellow text on blue background"; tput sgr0 |
| 通常建议为浅色前景色文本设置 粗体 属性。 |
tput sgr0 将终端设置恢复为正常。省略此项会导致该特定终端的所有后续输出都保持蓝色。
| 由于 tput sgr0 在某些情况下无法恢复终端设置，因此 echo -ne \E[0m 可能是更好的选择。 |
使用以下模板编写彩色背景上的彩色文本。 echo -e '\E[COLOR1;COLOR2m在这里输入一些文本' “\E[” 开始转义序列。分号分隔的数字 “COLOR1” 和 “COLOR2” 根据下表指定前景色和背景色。（数字的顺序无关紧要，因为前景色和背景色数字落在不重叠的范围内。）“m” 终止转义序列，文本紧随其后开始。 另请注意，单引号 括起 echo -e 后的命令序列的其余部分。 |
下表中的数字适用于 rxvt 终端。对于其他终端仿真器，结果可能会有所不同。
示例 36-15. 回显彩色文本
#!/bin/bash
# color-echo.sh: Echoing text messages in color.
# Modify this script for your own purposes.
# It's easier than hand-coding color.
black='\E[30;47m'
red='\E[31;47m'
green='\E[32;47m'
yellow='\E[33;47m'
blue='\E[34;47m'
magenta='\E[35;47m'
cyan='\E[36;47m'
white='\E[37;47m'
alias Reset="tput sgr0" # Reset text attributes to normal
#+ without clearing screen.
cecho () # Color-echo.
# Argument $1 = message
# Argument $2 = color
{
local default_msg="No message passed."
# Doesn't really need to be a local variable.
message=${1:-$default_msg} # Defaults to default message.
color=${2:-$black} # Defaults to black, if not specified.
echo -e "$color"
echo "$message"
Reset # Reset to normal.
return
}
# Now, let's try it out.
# ----------------------------------------------------
cecho "Feeling blue..." $blue
cecho "Magenta looks more like purple." $magenta
cecho "Green with envy." $green
cecho "Seeing red?" $red
cecho "Cyan, more familiarly known as aqua." $cyan
cecho "No color passed (defaults to black)."
# Missing $color argument.
cecho "\"Empty\" color passed (defaults to black)." ""
# Empty $color argument.
cecho
# Missing $message and $color arguments.
cecho "" ""
# Empty $message and $color arguments.
# ----------------------------------------------------
echo
exit 0
# Exercises:
# ---------
# 1) Add the "bold" attribute to the 'cecho ()' function.
# 2) Add options for colored backgrounds. |
示例 36-16. “赛马” 游戏
#!/bin/bash
# horserace.sh: Very simple horserace simulation.
# Author: Stefano Palmeri
# Used with permission.
################################################################
# Goals of the script:
# playing with escape sequences and terminal colors.
#
# Exercise:
# Edit the script to make it run less randomly,
#+ set up a fake betting shop . . .
# Um . . . um . . . it's starting to remind me of a movie . . .
#
# The script gives each horse a random handicap.
# The odds are calculated upon horse handicap
#+ and are expressed in European(?) style.
# E.g., odds=3.75 means that if you bet $1 and win,
#+ you receive $3.75.
#
# The script has been tested with a GNU/Linux OS,
#+ using xterm and rxvt, and konsole.
# On a machine with an AMD 900 MHz processor,
#+ the average race time is 75 seconds.
# On faster computers the race time would be lower.
# So, if you want more suspense, reset the USLEEP_ARG variable.
#
# Script by Stefano Palmeri.
################################################################
E_RUNERR=65
# Check if md5sum and bc are installed.
if ! which bc &> /dev/null; then
echo bc is not installed.
echo "Can\'t run . . . "
exit $E_RUNERR
fi
if ! which md5sum &> /dev/null; then
echo md5sum is not installed.
echo "Can\'t run . . . "
exit $E_RUNERR
fi
# Set the following variable to slow down script execution.
# It will be passed as the argument for usleep (man usleep)
#+ and is expressed in microseconds (500000 = half a second).
USLEEP_ARG=0
# Clean up the temp directory, restore terminal cursor and
#+ terminal colors -- if script interrupted by Ctl-C.
trap 'echo -en "\E[?25h"; echo -en "\E[0m"; stty echo;\
tput cup 20 0; rm -fr $HORSE_RACE_TMP_DIR' TERM EXIT
# See the chapter on debugging for an explanation of 'trap.'
# Set a unique (paranoid) name for the temp directory the script needs.
HORSE_RACE_TMP_DIR=$HOME/.horserace-`date +%s`-`head -c10 /dev/urandom \
| md5sum | head -c30`
# Create the temp directory and move right in.
mkdir $HORSE_RACE_TMP_DIR
cd $HORSE_RACE_TMP_DIR
# This function moves the cursor to line $1 column $2 and then prints $3.
# E.g.: "move_and_echo 5 10 linux" is equivalent to
#+ "tput cup 4 9; echo linux", but with one command instead of two.
# Note: "tput cup" defines 0 0 the upper left angle of the terminal,
#+ echo defines 1 1 the upper left angle of the terminal.
move_and_echo() {
echo -ne "\E[${1};${2}H""$3"
}
# Function to generate a pseudo-random number between 1 and 9.
random_1_9 ()
{
head -c10 /dev/urandom | md5sum | tr -d [a-z] | tr -d 0 | cut -c1
}
# Two functions that simulate "movement," when drawing the horses.
draw_horse_one() {
echo -n " "//$MOVE_HORSE//
}
draw_horse_two(){
echo -n " "\\\\$MOVE_HORSE\\\\
}
# Define current terminal dimension.
N_COLS=`tput cols`
N_LINES=`tput lines`
# Need at least a 20-LINES X 80-COLUMNS terminal. Check it.
if [ $N_COLS -lt 80 ] || [ $N_LINES -lt 20 ]; then
echo "`basename $0` needs a 80-cols X 20-lines terminal."
echo "Your terminal is ${N_COLS}-cols X ${N_LINES}-lines."
exit $E_RUNERR
fi
# Start drawing the race field.
# Need a string of 80 chars. See below.
BLANK80=`seq -s "" 100 | head -c80`
clear
# Set foreground and background colors to white.
echo -ne '\E[37;47m'
# Move the cursor on the upper left angle of the terminal.
tput cup 0 0
# Draw six white lines.
for n in `seq 5`; do
echo $BLANK80 # Use the 80 chars string to colorize the terminal.
done
# Sets foreground color to black.
echo -ne '\E[30m'
move_and_echo 3 1 "START 1"
move_and_echo 3 75 FINISH
move_and_echo 1 5 "|"
move_and_echo 1 80 "|"
move_and_echo 2 5 "|"
move_and_echo 2 80 "|"
move_and_echo 4 5 "| 2"
move_and_echo 4 80 "|"
move_and_echo 5 5 "V 3"
move_and_echo 5 80 "V"
# Set foreground color to red.
echo -ne '\E[31m'
# Some ASCII art.
move_and_echo 1 8 "..@@@..@@@@@...@@@@@.@...@..@@@@..."
move_and_echo 2 8 ".@...@...@.......@...@...@.@......."
move_and_echo 3 8 ".@@@@@...@.......@...@@@@@.@@@@...."
move_and_echo 4 8 ".@...@...@.......@...@...@.@......."
move_and_echo 5 8 ".@...@...@.......@...@...@..@@@@..."
move_and_echo 1 43 "@@@@...@@@...@@@@..@@@@..@@@@."
move_and_echo 2 43 "@...@.@...@.@.....@.....@....."
move_and_echo 3 43 "@@@@..@@@@@.@.....@@@@...@@@.."
move_and_echo 4 43 "@..@..@...@.@.....@.........@."
move_and_echo 5 43 "@...@.@...@..@@@@..@@@@.@@@@.."
# Set foreground and background colors to green.
echo -ne '\E[32;42m'
# Draw eleven green lines.
tput cup 5 0
for n in `seq 11`; do
echo $BLANK80
done
# Set foreground color to black.
echo -ne '\E[30m'
tput cup 5 0
# Draw the fences.
echo "++++++++++++++++++++++++++++++++++++++\
++++++++++++++++++++++++++++++++++++++++++"
tput cup 15 0
echo "++++++++++++++++++++++++++++++++++++++\
++++++++++++++++++++++++++++++++++++++++++"
# Set foreground and background colors to white.
echo -ne '\E[37;47m'
# Draw three white lines.
for n in `seq 3`; do
echo $BLANK80
done
# Set foreground color to black.
echo -ne '\E[30m'
# Create 9 files to stores handicaps.
for n in `seq 10 7 68`; do
touch $n
done
# Set the first type of "horse" the script will draw.
HORSE_TYPE=2
# Create position-file and odds-file for every "horse".
#+ In these files, store the current position of the horse,
#+ the type and the odds.
for HN in `seq 9`; do
touch horse_${HN}_position
touch odds_${HN}
echo \-1 > horse_${HN}_position
echo $HORSE_TYPE >> horse_${HN}_position
# Define a random handicap for horse.
HANDICAP=`random_1_9`
# Check if the random_1_9 function returned a good value.
while ! echo $HANDICAP | grep [1-9] &> /dev/null; do
HANDICAP=`random_1_9`
done
# Define last handicap position for horse.
LHP=`expr $HANDICAP \* 7 + 3`
for FILE in `seq 10 7 $LHP`; do
echo $HN >> $FILE
done
# Calculate odds.
case $HANDICAP in
1) ODDS=`echo $HANDICAP \* 0.25 + 1.25 | bc`
echo $ODDS > odds_${HN}
;;
2 | 3) ODDS=`echo $HANDICAP \* 0.40 + 1.25 | bc`
echo $ODDS > odds_${HN}
;;
4 | 5 | 6) ODDS=`echo $HANDICAP \* 0.55 + 1.25 | bc`
echo $ODDS > odds_${HN}
;;
7 | 8) ODDS=`echo $HANDICAP \* 0.75 + 1.25 | bc`
echo $ODDS > odds_${HN}
;;
9) ODDS=`echo $HANDICAP \* 0.90 + 1.25 | bc`
echo $ODDS > odds_${HN}
esac
done
# Print odds.
print_odds() {
tput cup 6 0
echo -ne '\E[30;42m'
for HN in `seq 9`; do
echo "#$HN odds->" `cat odds_${HN}`
done
}
# Draw the horses at starting line.
draw_horses() {
tput cup 6 0
echo -ne '\E[30;42m'
for HN in `seq 9`; do
echo /\\$HN/\\" "
done
}
print_odds
echo -ne '\E[47m'
# Wait for a enter key press to start the race.
# The escape sequence '\E[?25l' disables the cursor.
tput cup 17 0
echo -e '\E[?25l'Press [enter] key to start the race...
read -s
# Disable normal echoing in the terminal.
# This avoids key presses that might "contaminate" the screen
#+ during the race.
stty -echo
# --------------------------------------------------------
# Start the race.
draw_horses
echo -ne '\E[37;47m'
move_and_echo 18 1 $BLANK80
echo -ne '\E[30m'
move_and_echo 18 1 Starting...
sleep 1
# Set the column of the finish line.
WINNING_POS=74
# Define the time the race started.
START_TIME=`date +%s`
# COL variable needed by following "while" construct.
COL=0
while [ $COL -lt $WINNING_POS ]; do
MOVE_HORSE=0
# Check if the random_1_9 function has returned a good value.
while ! echo $MOVE_HORSE | grep [1-9] &> /dev/null; do
MOVE_HORSE=`random_1_9`
done
# Define old type and position of the "randomized horse".
HORSE_TYPE=`cat horse_${MOVE_HORSE}_position | tail -n 1`
COL=$(expr `cat horse_${MOVE_HORSE}_position | head -n 1`)
ADD_POS=1
# Check if the current position is an handicap position.
if seq 10 7 68 | grep -w $COL &> /dev/null; then
if grep -w $MOVE_HORSE $COL &> /dev/null; then
ADD_POS=0
grep -v -w $MOVE_HORSE $COL > ${COL}_new
rm -f $COL
mv -f ${COL}_new $COL
else ADD_POS=1
fi
else ADD_POS=1
fi
COL=`expr $COL + $ADD_POS`
echo $COL > horse_${MOVE_HORSE}_position # Store new position.
# Choose the type of horse to draw.
case $HORSE_TYPE in
1) HORSE_TYPE=2; DRAW_HORSE=draw_horse_two
;;
2) HORSE_TYPE=1; DRAW_HORSE=draw_horse_one
esac
echo $HORSE_TYPE >> horse_${MOVE_HORSE}_position
# Store current type.
# Set foreground color to black and background to green.
echo -ne '\E[30;42m'
# Move the cursor to new horse position.
tput cup `expr $MOVE_HORSE + 5` \
`cat horse_${MOVE_HORSE}_position | head -n 1`
# Draw the horse.
$DRAW_HORSE
usleep $USLEEP_ARG
# When all horses have gone beyond field line 15, reprint odds.
touch fieldline15
if [ $COL = 15 ]; then
echo $MOVE_HORSE >> fieldline15
fi
if [ `wc -l fieldline15 | cut -f1 -d " "` = 9 ]; then
print_odds
: > fieldline15
fi
# Define the leading horse.
HIGHEST_POS=`cat *position | sort -n | tail -1`
# Set background color to white.
echo -ne '\E[47m'
tput cup 17 0
echo -n Current leader: `grep -w $HIGHEST_POS *position | cut -c7`\
" "
done
# Define the time the race finished.
FINISH_TIME=`date +%s`
# Set background color to green and enable blinking text.
echo -ne '\E[30;42m'
echo -en '\E[5m'
# Make the winning horse blink.
tput cup `expr $MOVE_HORSE + 5` \
`cat horse_${MOVE_HORSE}_position | head -n 1`
$DRAW_HORSE
# Disable blinking text.
echo -en '\E[25m'
# Set foreground and background color to white.
echo -ne '\E[37;47m'
move_and_echo 18 1 $BLANK80
# Set foreground color to black.
echo -ne '\E[30m'
# Make winner blink.
tput cup 17 0
echo -e "\E[5mWINNER: $MOVE_HORSE\E[25m"" Odds: `cat odds_${MOVE_HORSE}`"\
" Race time: `expr $FINISH_TIME - $START_TIME` secs"
# Restore cursor and old colors.
echo -en "\E[?25h"
echo -en "\E[0m"
# Restore echoing.
stty echo
# Remove race temp directory.
rm -rf $HORSE_RACE_TMP_DIR
tput cup 19 0
exit 0 |
另请参见 示例 A-21、示例 A-44、示例 A-52 和 示例 A-40。
 | 然而，所有这一切都存在一个主要问题。ANSI 转义序列绝对是 不可移植的。 在某些终端仿真器（或控制台）上运行良好的代码，在其他终端上可能运行不同，甚至根本无法运行。在脚本作者的机器上看起来令人惊艳的 “着色” 脚本，在别人的机器上可能会产生无法读取的输出。这在一定程度上损害了着色脚本的实用性，并可能将这项技术降级为一种噱头。着色脚本可能不适合商业环境，也就是说，您的主管可能不赞成。 |
Alister 的 ansi-color 实用程序（基于 Moshe Jacobson 的 color 实用程序）大大简化了 ANSI 转义序列的使用。它用简洁而逻辑的语法代替了刚刚讨论的笨拙结构。
Henry/teikedvl 也创建了一个实用程序 (http://scriptechocolor.sourceforge.net/) 来简化着色脚本的创建。