自己写的一些shell脚本

1 BEGIN{
2     for(n=1;n<=5;n++)
3     print "2^"n,2**n
4 }
5 ###awk   -f    for.awk     

1 [zengqingfu@zengqingfu ~]$ vim shell_scripts.sh 
2 
3 [ -f aaaaa ]&&echo "aaaaa is a file" ||echo "aaaaa is a directory"
4 [ 10 -gt 10 ] && echo "10 is greater than 10" || echo "10 is not greater than 10"
5 echo $?
6 [ 10 -eq 10 ]
7 echo $?
8 FreeMem=`free -m | grep cache: |awk ‘{print $3}‘`
9 echo $FreeMem

  1 [zengqingfu@zengqingfu shell_script]$ cat quiz 
  2 #!/bin/bash
  3 #remove the # on the following line to turn on debugging
  4 #set -o xtrace
  5 
  6 #==========================
  7 function initialize (){
  8 trap ‘summarize;exit 0‘ INT    #Handle user interrupts
  9 num_ques=0            #Number of questions asked so far
 10 num_correct=0            #Number answered correctly so far 
 11 first_time=true            #true until first question is asked
 12 cd ${QUIZDIR:=~/quiz} || exit 2
 13 }
 14 
 15 #=========================
 16 function choose_subj (){
 17 subjects=($(ls))
 18 PS3="Choose a subject for the quiz from the preceding list:"
 19 select Subject in ${subjects[*]};do
 20     if [[ -z "$Subject" ]];then
 21     echo "No subject chosen. Bye." >&2
 22     exit 1
 23     fi
 24     echo $Subject
 25     return 0
 26 done
 27 }
 28 
 29 #===========================
 30 function exchange (){
 31 temp_value=${questions[$1]}
 32 questions[$1]=${questions[$2]}
 33 questions[$2]=$temp_value
 34 }
 35 
 36 #===========================
 37 function scramble (){
 38 declare -i index quescount
 39 questions=($(ls))
 40 quescount=${#questions[*]}    #Number of elements
 41 ((index=quescount-1))
 42 while [[ $index > 0 ]];do
 43     ((target=RANDOM % index))
 44     exchange $target $index
 45     ((index -= 1))
 46 done
 47 }
 48 
 49 #==========================
 50 function ask (){
 51 exec 3<$1
 52 read -u3 ques || exit 2
 53 read -u3 num_opts || exit 2
 54 
 55 index=0
 56 choices=()
 57 while (( index < num_opts )) ; do
 58     read -u3 next_choice || exit 2
 59     choices=("${choices[@]}" "$next_choice")
 60     ((index += 1 ))
 61 done
 62 read -u3 correct_answer || exit 2
 63 exec 3<&-
 64 
 65 if [[ $first_time = true ]];then
 66     first_time=false
 67     echo -e "You may press the interrupt key at any time to quit.\n"
 68 fi
 69 
 70 PS3=$ques" "    #Make $ques the prompt for select
 71         #and add some spaces for legibility
 72 select answer in "${choices[@]}";do
 73     if [[ -z "$answer"  ]];then
 74     echo "Not a valid choice.Please choose again."
 75     elif [[ "$answer" = "$correct_answer" ]];then
 76      echo ‘Correct!‘
 77     return 1
 78     else 
 79     echo "No,the answer is $correct_answer."
 80     return 0
 81     fi
 82 done
 83 }
 84 
 85 #=========================
 86 function summarize (){
 87 echo             #skip a line
 88 if ((num_ques == 0 ));then
 89     echo "You did not answer any questions"
 90     exit 0
 91 fi
 92 
 93 ((percent=num_correct*100/num_ques))
 94 echo "You answered $num_correct questions correctly,out of \
 95 $num_ques total questions."
 96 echo "Your score is $percent percent."
 97 }
 98 
 99 #============================
100 # main program
101 initialize        #Step 1 in top-level design
102 
103 subject=$(choose_subj)   #Step 2
104 [[ $? -eq 0 ]] || exit 2   #If no valid choice,exit
105 
106 cd $subject || exit 2     #Step 3
107 echo             #skip  a line
108 scramble         #step 4
109 
110 for ques in ${questions[*]};do    #step 5
111     ask $ques
112     result=$?
113     (( num_ques=numques+1 ))
114     if [[ $result == 1 ]];then
115     (( num_correct +=1 ))
116     fi
117     echo                     #skip a line between questions
118     sleep ${QUIZDELAY:=1}
119 done
120 
121 
122 summarize                      #step 6
123 exit 0

[zengqingfu@zengqingfu shell_script]$ cd ..
[zengqingfu@zengqingfu ~]$ ll quiz/
总用量 40
drwxrwxr-x. 2 zengqingfu zengqingfu 4096 3月 17 10:23 art
drwxrwxr-x. 2 zengqingfu zengqingfu 4096 3月 17 10:25 biology
drwxrwxr-x. 2 zengqingfu zengqingfu 4096 3月 17 10:25 chemistry
drwxrwxr-x. 2 zengqingfu zengqingfu 4096 3月 17 10:25 Chinese
drwxrwxr-x. 2 zengqingfu zengqingfu 4096 3月 17 10:23 engineering
drwxrwxr-x. 2 zengqingfu zengqingfu 4096 3月 17 10:25 english
drwxrwxr-x. 2 zengqingfu zengqingfu 4096 3月 17 10:26 history
drwxrwxr-x. 2 zengqingfu zengqingfu 4096 3月 17 10:33 math
drwxrwxr-x. 2 zengqingfu zengqingfu 4096 3月 17 10:26 physics
drwxrwxr-x. 2 zengqingfu zengqingfu 4096 3月 17 10:24 politics

问题保存在脚本父目录的下面，分为好几类：

只要执行quiz脚本，制定好问题quiz所在的路径，脚本就能读取问题，然后你回答问题，而正确答案已经在问题的4个选项后面写好了，将你回答的与正确答案一比较，就能判断正误。