C-shell精华程式

1. switch 的用法，注意每一个 case 必须要以 breaksw 结尾
　 否则会继续执行下一个 case 的命令
(1) 另外， $<的意思是取得使用者的 stand input
(2) echo 若加上 -n 的选项，则游标会停留在该行最后

echo -n "Input one color: "
set STOPLIGHT = $<
switch ($STOPLIGHT)
case red:
echo "red"
breaksw
case orange:
echo "orange"
breaksw
case green:
echo "green"
breaksw
default:
echo "you input $STOPLIGHT"
endsw

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2. 利用 set 来取得变数， set ABC = "I am ABC"
也可以利用 `command` 来取得命令
且外，case 也可以用万用字元 * 来代替

set VER = `uname -r`
switch ($VER)
case 5.5:
echo "run the setup of $VER"
breaksw
case 5.3:
echo "run the setup of $VER"
breaksw
case 5.*:
echo "like 5.x"
breaksw
case 4.*:
echo "like 4.x"
breaksw
default:
echo "no idea"
endsw

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3. if 的语法，比较数字

set n1 = 1
set n2 = 2
if ($n1 == $n2) then
echo "$n1 Equal $n2"
else
echo "$n1 Not Equal $n2"
endif


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4. if 的语法，比较字串

set n1 = abcdef
set n2 = abcde
if ($n1 == $n2) then
echo "$n1 Equal $n2"
else
echo "$n1 Not Equal $n2"
endif


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5. if 的语法，比较相似的字串

set n1 = abcdef
set n2 = abcde
if ($n1 =~ $n2) then
echo "$n1 Like $n2"
else
echo "$n1 Not Like $n2"
endif


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6. if 的语法，比较数字的大小

set n1 = 1
set n2 = 2
if ($n1 > $n2) then
echo "$n1 > $n2"
else
echo "$n1 <$n2"
endif


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7. 每分钟执行一次的程式

# mm 等于当天时间的【分钟】数
set mm = `date | cut -d' ' -f4 | cut -d: -f2`

if ( -r $0.out ) then
rm $0.out
touch $0.out
else
touch $0.out
endif

while ( $mm <= 16 )
set mm = `date | cut -d' ' -f4 | cut -d: -f2`
echo "$mm now is `date`"
sleep 60
＃e cho "$mm now is `date`" >> $0.out
end
echo "Over" >> $0.out


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8. 一个回圈的范例，并且利用 expr 去作加的动作
回圈的语法如下：
foreach number (1 2 3)
echo $number
end

set counter = 0
while ($counter <= 10)
echo "sleeping for 5 seconds"
sleep 5
counter = `expr $counter + 1 `
end


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9. 设定一个用当天月份与日期作为档案名称的程式
如今天是 10/02 , 则 $prefix 会等于 该程式 + 1002
date.csh1002

set prefix = `basename $0``date '+ %m%d'`
echo $0
echo $prefix


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10. 移除在 foreach 回圈内指定的档案内的 font 字串


foreach file ([b,e,g,h,s]*.html)
echo -n "Processing $file, remove the line number `grep -n font $file`"

# $log 表示这个 $file 有几个 font 字串
set log = `grep -c font $file`
if ( $log == '0' ) then
echo ", pass $file"
else
# 先找出该档案的第一次出现 font 的行数，如果 3，则 $cmd = 3d
set cmd = `grep -n font $file | cut -d: -f1 | head -1`d
# 利用 sed 去执行删除的动作，并把结果输出到 ${file}1
sed $cmd $file > ${file}1
# 如果 ${file}1 没有资料，则 passing
if ( -z ${file}1 ) then
echo " , ${file}1 is zero"
else
cp ${file}1 $file
rm {$file}1
echo " , $file remove ok"
endif
endif
end

# 后来看过 sed 的更进一步用法，发现先前写的太笨了，试试这个
# sed /font/d $file > ${file}1
# 一次 OK, 我真是大笨蛋

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11. 功能：将指定的档案中，出现第一次【回】的那一行，加上

foreach file (sky*.html)
set filetitle = ftitle
# 主要部份为 sed 部份 s/^ *// 表示将该行第一个字元前的空白删除
echo "" > $ftitle

# 将刚刚那一行，再插回去
head -1 $file > ${file}head
sed 1d $file > ${file}1
cat $ftitle >> ${file}head
cat ${file}1 >> ${file}head
cp ${file}head $file
rm ${file}1
rm $ftitle
rm ${file}head

echo "$file ok"
end

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12. 一个实际建立一个 ftp server 的程式
　　里面包括许多应用，相当有参考价值
( 未完成 )

set path = ( /usr/bin /usr/sbin )
#
set true = `grep -c ftp /etc/passwd`
if ( $true == 0 ) then
echo "no ftp user in your system"
echo -n "do you want to create the ftp user? "
set answer = $<
if ($answer == 'y' || $answer == 'Y') then
set maxid = `sort /etc/passwd | tail -1 | cut -d: -f3`
echo $maxid
set newid = `expr $maxid + 1`
echo $newid
echo "/usr/sbin/useradd -d /home1/ftp -u $newid -s /etc/false ftp"
endif
else
echo "Good. Your system already has the ftp user. "
set ftphome = `grep ftp: /etc/passwd | cut -d: -f6`
echo $ftphome
endif

if ( -z $ftphome ) then
echo "ftphome must be non-null"
exit 2
endif

if ( $ftphome == "/usr" || $ftphome == "/" ) then
echo "ftphome can't be / or /usr"
exit 2
endif

# create the ftp home directory
if ( ! -d $ftphome ) then
echo "mkdir $ftphome"
endif

echo "Setting up the ftphome for SunOS `uname -r`"

if ( ! -d $ftphome ) then
echo "mkdir -p $ftphome/usr/bin"
endif

cp /bin/ls $ftphome/usr/bin

chmod 111 $ftphome/usr/bin/ls
chown root $ftphome/usr/bin
chmod 555 $ftphome/usr/bin

if ( -r $ftphome/bin ) then
mv -f $ftphome/bin $ftphome/Obin
endif
ln -s usr/bin $ftphome


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13. 取得该使用者的 UID

if ( $#argv == 0 ) then
echo "$0 usage: $1 username"
exit 2
endif

set uid = `grep $1 /etc/passwd | cut -d: -f3`
echo $uid


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14. 将指定档案内的 html 取代成 htm

foreach file ( *.html )
echo "Processing $file ..."
sed s/html/htm/ $file > ${file}1
cp ${file}1 $file
rm ${file}1
end


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15. 一个简简单单的范例，看看就好

#!/bin/csh -f
echo .................
echo WELCOME to \* TAPE COPY \*
echo .................
echo Enter your name:
# $ set name = $<
echo " "
echo Hi $name \!
set D = `date`
echo Today\'s date is $D[1] $D[2] $D[3]
if ($D[1] == Mon) then
echo -------------------------------------------------------------
echo Today is $D[1]day $name, it\'s time to copy your directorys\!
echo -------------------------------------------------------------
else
echo -------------------------------------------------------------
echo Today is $D[1]day $name, no tape copies today\!
echo -------------------------------------------------------------
endif


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16. 一个 finger 的程式

set FINGER = "/usr/ucb/finger"

if ( -x $FINGER ) then
if ( $#argv == 0 ) then
cat < ---------------------------------
Hahahah ....
---------------------------------
TAG
else
$FINGER "$*"
endif

else
echo "Cannot find finger on this system."
endif


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17. 取得变数的方法

set W = `who -r`
echo $W[9]



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18. 更改档案名称，将 *.html --> *.htm

# rename *.html to *.htm
echo -n "This will change *.html to *.htm. Can I continue ? (y/n) : "
set input = $<
if ( $input != "y" && $input != "Y" ) then
echo "Ok. Quit..."
exit 2
endif

foreach file ( *.html )
echo "Processing $file to `basename $file .html`.htm "
mv $file `basename $file .html`.htm
end

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19. 更改档案名称，将 *.htm --> *.html

echo -n "This will change *.htm to *.html. Can I continue ? (y/n) : "
set input = $<
if ( $input != "y" && $input != "Y" ) then
echo "Ok. Quit..."
exit 2
endif

# rename *.htm to *.html
foreach file ( *.htm )
echo "Processing $file to `basename $file .htm`.html "
mv $file `basename $file .htm`.html
end

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20. 将大写的档名改成小写的档名
tr string1 string2 会将 standard input 的字串，
所对应到的 string1, 都以 string2 取代

foreach file ( * )
mv $file `echo $file | tr '[A-Z]' '[a-z]'`
end

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21. 将小写的档名改成大写的档名

foreach file (*)
mv $file `echo $file | tr '[a-z]' '[A-Z]'`
end