1: set -f
 2: choice=0

 3: while [ 0 ]
 4: do

 5:  
 6: echo "1.Display crontab jobs."

 7:  
 8: echo "2.Insert a job."

 9:  
 10: echo "3.Remove a job."

 11:  
 12: echo "4.Exit."

 13:  
 14: echo -n "Select>"

 15:  
 16: read choice

 17:  
 18: case $choice in

 19:  
 20: 1) line=1

 21:  
 22: crontab -l > $HOME/.jobs

 23:  
 24: res="`wc -l $HOME/.jobs`"

 25:  
 26: set - $res;lines=$1;

 27:  
 28: while [ $line -le $lines ]

 29:  
 30: do

 31:  
 32: res="`head -$line $HOME/.jobs | tail -1`"

 33:  
 34: set - $res;disp=" ";

 35:  
 36: for arg

 37:  
 38: do

 39:  
 40: if [ "$arg" = '*' ]

 41:  
 42: then

 43:  
 44: disp="$disp Any"

 45:  
 46: else

 47:  
 48: disp="$disp $arg"

 49:  
 50: fi

 51:  
 52: done

 53:  
 54: set - $disp

 55:  
 56: echo "JOB $line-->"

 57:  
 58: echo "minute: $1";shift;

 59:  
 60: echo "Hour: $1";shift;

 61:  
 62: echo "Date: $1/$2";shift;shift;

 63:  
 64: echo "Day of week: $1";shift;

 65:  
 66: echo "Command:$*"

 67:  
 68: line=`expr $line + 1`

 69:  
 70: done;;

 71:  
 72: 2) crontab -l >$HOME/.newjobs

 73:  
 74: selection=0

 75:  
 76: minutes="any"

 77:  
 78: hours="any"

 79:  
 80: monthday="any"

 81:  
 82: month="any"

 83:  
 84: weekday="any"

 85:  
 86: while [ $selection -ne 7 ]

 87:  
 88: do

 89:  
 90: echo "1.Set the command(-obligatory):"

 91:  
 92: echo "Set periodicity of command."

 93:  
 94: echo "2.Set minutes:0-59"

 95:  
 96: echo "3.Set hours:0-23"

 97:  
 98: echo "4.Set day of month:1-31"

 99:  
 100: echo "5.Set month:1-12"

 101:  
 102: echo "6.Set day of week:Mon-Sun"

 103:  
 104: echo "7.Ready."

 105:  
 106: echo -n "Enter>"

 107:  
 108: read selection

 109:  
 110: case $selection in

 111:  
 112: 1)echo -n "Enter>"

 113:  
 114: read command;;

 115:  
 116: 2) echo -n "If more than one choice,seperate by comma..Enter>"

 117:  
 118: read minutes;;

 119:  
 120: 3) echo -n "If more than one choice,seperate by comma..Enter>"

 121:  
 122: read hours;;

 123:  
 124: 4) echo -n "If more than one choice,seperate by comma..Enter>"

 125:  
 126: read monthday;;

 127:  
 128: 5) echo -n "If more than one choice,seperate by comma..Enter>"

 129:  
 130: read month;;

 131:  
 132: 6) echo -n "If more than one choice,seperate by comma..Enter>"

 133:  
 134: read weekday;;

 135:  
 136: 7) break;;

 137:  
 138: *) continue;;

 139:  
 140: esac

 141:  
 142: done

 143:  
 144: periodicity=" "

 145:  
 146: for inst in $minutes $hours $monthday $month $weekday

 147:  
 148: do

 149:  
 150: if [ "$inst" = "any" ]

 151:  
 152: then

 153:  
 154: periodicity="$periodicity *"

 155:  
 156: else

 157:  
 158: periodicity="$periodicity $inst"

 159:  
 160: fi

 161:  
 162: done

 163:  
 164: echo "$periodicity $command">>$HOME/.newjobs

 165:  
 166: crontab $HOME/.newjobs;;

 167:  
 168: 3) crontab -l >$HOME/.jobs

 169:  
 170: echo "Job to remove"

 171:  
 172: echo -n "Enter Job's number as listed above>"

 173:  
 174: read jobnmb

 175:  
 176: res="`wc -l $HOME/.jobs`"

 177:  
 178: set - $res;

 179:  
 180: rest=`expr $1 - $jobnmb`

 181:  
 182: jobnmb=`expr $jobnmb - 1`

 183:  
 184: head -$jobnmb $HOME/.jobs | cat >$HOME/.njobs

 185:  
 186: tail -$rest $HOME/.jobs | cat >>$HOME/.njobs

 187:  
 188: crontab $HOME/.njobs;;

 189:  
 190: 4) rm $HOME/.jobs $HOME/.newjobs

 191:  
 192: exit;;

 193:  
 194: *) continue;;

 195:  
 196: esac

 197:  
 198: done