12.8 本章习题

#!/bin/bash
echo -e "Your name is ==> $（whoami）"
echo -e "The current directory is ==> $（pwd）"

#!/bin/bash
read -p "Pleas input your birthday （MMDD, ex> 0709）: " bir
now=`date +%m%d`
if [ "$bir" == "$now" ]; then
echo "Happy Birthday to you!!!"
elif [ "$bir" -gt "$now" ]; then
year=`date +%Y`
total_d=$（（$（（`date --date="$year$bir" +%s`-`date +%s`））/60/60/24））
echo "Your birthday will be $total_d later"
else
year=$（（`date +%Y`+1））
total_d=$（（$（（`date --date="$year$bir" +%s`-`date +%s`））/60/60/24））
echo "Your birthday will be $total_d later"
fi

#!/bin/bash
read -p "Please input an integer number: " number
i=0
s=0
while [ "$i" != "$number" ]
do
i=$（（$i+1））
s=$（（$s+$i））
done
echo "the result of '1+2+3+...$number' is ==> $s"

#!/bin/bash
if [ ! -e logical ]; then
touch logical
echo "Just make a file logical"
exit 1
elif [ -e logical ] && [ -f logical ]; then
rm logical
mkdir logical
echo "remove file ==> logical"
echo "and make directory logical"
exit 1
elif [ -e logical ] && [ -d logical ]; then
rm -rf logical
echo "remove directory ==> logical"
exit 1
else
echo "Does here have anything?"
fi

#!/bin/bash
accounts=`cat /etc/passwd | cut -d':' -f1`
for account in $accounts
do
declare -i i=$i+1
echo "The $i account is \"$account\" "
done