$date_offset.sh
usage()
{
echo"
使用方法:"
echo"
date_offset.shYYYY/MM/DDoffset"
echo"
/n举例:"
echo"
date_offset.sh2001/10/01-1返回:2001/09/30"
echo"
date_offset.sh2001/10/015返回:2001/10/06/n"
exit2
}
yesterday()
{
YEAR=`echo$1|awk-F"
/"
'
{print$1}'
`
MONTH=`echo$1|awk-F"
/"
'
{print$2}'
`
DAY=`echo$1|awk-F"
/"
'
{print$3}'
`
if[$DAY-eq1]
then
if[$MONTH-eq1]
then
YEAR=`expr$YEAR-1`
MONTH=12
else
MONTH=`expr$MONTH-1`
fi
DAY=`echo/`cal$MONTH$YEAR/`|tail-n1|awk'
{print$NF}'
`
else
DAY=`expr$DAY-1`
fi
echo"
$YEAR$MONTH$DAY"
|awk'
{if(length($2)==1)$2=0$2;if(length($3)==1)$3=0$3;printf"
%s/%s/%s"
,$1,$2,$3}'
}
tomorrow()
{
YEAR=`echo$1|awk-F"
/"
'
{print$1}'
`
MONTH=`echo$1|awk-F"
/"
'
{print$2}'
`
DAY=`echo$1|awk-F"
/"
'
{print$3}'
`
LASTDAY=`echo/`cal$MONTH$YEAR/`|tail-n1|awk'
{print$NF}'
`
if[$DAY-eq$LASTDAY]
then
if[$MONTH-eq12]
then
YEAR=`expr$YEAR+1`
MONTH=1
else
MONTH=`expr$MONTH+1`
fi
DAY=1
else
DAY=`expr$DAY+1`
fi
echo"
$YEAR$MONTH$DAY"
|awk'
{if(length($2)==1)$2=0$2;if(length($3)==1)$3=0$3;printf"
%s/%s/%s"
,$1,$2,$3}'
}
#检查参数数目
if[$#-ne2]
then
echo"
/n调用出错:参数数目不对!/n"
usage
fi
#检查参数1长度
if[`exprlength$1`-ne10]
then
echo"
/n调用出错:日期格式不正确!/n"
usage
fi
TMP_YEAR=`echo$1|awk-F"
/"
'
{print$1}'
`
TMP_MONTH=`echo$1|awk-F"
/"
'
{print$2}'
`
TMP_DAY=`echo$1|awk-F"
/"
'
{print$3}'
`
if!expr$TMP_YEAR+$TMP_MONTH+$TMP_DAY>/dev/null2>&1
then
echo"
/n调用出错:日期格式不正确!/n"
usage
fi
if[`exprlength$TMP_YEAR`-ne4]
then
echo"
/n调用出错:日期格式不正确!/n"
usage
fi
if[$TMP_MONTH-lt1]||[$TMP_MONTH-gt12]
then
echo"
/n调用出错:日期格式不正确!/n"
usage
fi
LAST_DAY=`echo/`cal$TMP_MONTH$TMP_YEAR/`|tail-n1|awk'
{print$NF}'
`
if[$TMP_DAY-lt1]||[$TMP_DAY-gt$LAST_DAY]
then
echo"
/n调用出错:日期格式不正确!/n"
usage
fi
#检查参数2是否为数值
expr$2+0>/dev/null2>&1
if[!$?]
then
echo"
/n调用出错:日期偏移量应为整数值!/n"
usage
fi
TMP_DATE=$1
if[$2-lt0]
then
INC=-1
COUNT=$2
else
INC=1
COUNT=`expr0-$2`
fi
while[$COUNT-lt0]
do
if[$INC-gt0]
then
TMP_DATE=`tomorrow$TMP_DATE`
else
TMP_DATE=`yesterday$TMP_DATE`
fi
COUNT=`expr$COUNT+1`
done
echo$TMP_DATE
#在要SCO5.0.5下测试通过。