linux获取前一天的日期的脚本
yy=`date +%Y`
mm=`date +%m`dd=`date +%d`
if [ $dd = "01" ]
then
lm=`expr $mm - 1 `
if [ $lm -eq 0 ]
then
lm=12
yy=`expr $yy - 1 `
fi
case $lm in
1|3|5|7|8|10|12) Yesterday=31 ;;
4|6|9|11) Yesterday=30 ;;
2)
if [ ` expr $yy % 4 ` -eq 0 -a `expr $yy % 100 ` -ne 0 -o ` expr $yy % 400 ` -eq 0 ]
then Yesterday=29
else Yesterday=28
fi ;;
esac
mm=$lm
else
Yesterday=`expr $dd - 1 `
fi
case $Yesterday in
1|2|3|4|5|6|7|8|9) Yesterday='0'$Yesterday
esac
case $mm in
1|2|3|4|5|6|7|8|9) mm='0'$mm ;;
esac
Yesterday=$yy$mm$Yesterday
echo ''$Yesterday