date +%s 可以得到UNIX的时间戳;
用shell将时间字符串与时间戳互转:
date -d "2010-10-18 00:00:00" +%s 输出形如:1287331200
而时间戳转换为字符串可以这样做:
date -d @1287331200 "+%Y-%m-%d" 输出形如:2010-10-18
如果需要得到指定日期的前后几天,可以:
1、seconds=`date -d "2010-10-18 00:00:00" +%s` #得到时间戳
2、seconds_new=`expr $seconds + 86400` #加上一天的秒数86400
3、date_new=`date -d @$seconds_new "+%Y-%m-%d"` #获得指定日前加上一天的日前
- 第一种 使用date -d 选项
date +"%Y%m%d" -d "+n days" 今天的后n天日期
date +"%Y%m%d" -d "-n days" 今天的前n天日期
- 自己写函数
#!/bin/ksh
#获取昨天的日期
lastday()
{
Today=`date +%Y%m%d`
YEAR=`echo $Today|cut -c 1-4`
MONTH=`echo $Today|cut -c 5-6`
DAY=`echo $Today|cut -c 7-8`
if [ $DAY -eq 1 ]
then
if [ $MONTH -eq 1 ]
then
YEAR=`expr $YEAR - 1`
MONTH=12
else
MONTH=`expr $MONTH - 1`
fi
#如下两种方法皆可
#DAY=`echo \`cal $MONTH $YEAR\`|tail -n1|awk '{print $NF}'`
#
DAY=$(cal $MONTH $YEAR | tail -n2|sed -n 1,1p | awk '{print $NF}')
else
DAY=`expr $DAY - 1`
fi
LAST=$(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}')
}
GetLastDate()
{
TODAY=`date "+%Y %m %d"`
LASTDATE=`echo $TODAY|awk \
'{ \
Year=$1; Month=$2; Day=$3; \
M[1]=31; M[2]=28; M[3]=31; M[4]=30; M[5]=31; M[6]=30; \
M[7]=31; M[8]=31; M[9]=30; M[10]=31; M[11]=30; M[12]=31; \
if (Year%4==0 && (Year%100!=0 || Year%400==0)) M[2]=29; \
else M[2]=28; \
if (Day-1==0) \
{ \
if (Month-1==0) { Year-=1; Month=12; } \
else Month-=1; \
Day=M[Month]; \
} \
else Day-=1; \
printf("%04d%02d%02d", Year, Month, Day); \
}'`
}
echo "***************"
lastday
echo ${LAST}
echo "***************"
GetLastDate
echo ${LASTDATE}
-----------------------------------------------------------
常用日期格式
[root@localhost tmp]# date +"%F"
2012-06-08
[root@localhost tmp]# date +"%D"
06/08/12
[root@localhost tmp]# date +"%Y%m%d %H:%M:%S"
20120608 04:52:28
[root@localhost tmp]# date +"%Y%m%d"
20120608
[root@localhost tmp]# date +"%Y%m%d %H:%M:%S" -d "+1 hours"
20120608 05:52:43
[root@localhost tmp]# date +"%Y%m%d %H:%M:%S" -d "+1 days"
20120609 04:52:52
[root@localhost tmp]# date +"%Y%m%d %H:%M:%S" -d "+1 months"
20120708 04:52:56
[root@localhost tmp]# date +"%Y%m%d %H:%M:%S" -d "+1 years"
20130608 04:53:07
[root@localhost tmp]# date +"%T"
05:03:21
[root@localhost tmp]# date +"%F %T"
2012-06-08 05:03:34
[root@localhost tmp]# date +"%D %T"
06/08/12 05:03:39
[root@localhost riqi]# date +"%Y-%m-%d %H:%M:%S"
2012-07-18 05:17:01
[root@localhost riqi]# date +"%Y-%m-%d %H:%M:%S" -d "+10hour"
2012-07-18 15:17:16
[root@localhost riqi]# date +"%Y-%m-%d %H:%M:%S" -d "+24hour"
2012-07-19 05:17:37
[root@localhost riqi]# date +"%Y-%m-%d %H:%M:%S" -d "-24hour"
2012-07-17 05:17:45
[root@localhost riqi]# date +"%Y-%m-%d %H:%M:%S" -d "-20minute"
2012-07-18 04:58:00
[root@localhost riqi]# date +"%Y-%m-%d %H:%M:%S" -d "+20minute"
2012-07-18 05:38:05
[root@localhost riqi]# date +"%Y-%m-%d %H:%M:%S" -d "+2day"
2012-07-20 05:18:15
[root@localhost riqi]# date +"%Y-%m-%d %H:%M:%S" -d "-2day"
2012-07-16 05:18:19
[root@localhost riqi]# date +"%Y-%m-%d %H:%M:%S" -d "-2month"
2012-05-18 05:18:24
[root@localhost riqi]# date +"%Y-%m-%d %H:%M:%S" -d "+2month"
2012-09-18 05:18:28
[root@localhost riqi]# date +"%Y-%m-%d %H:%M:%S" -d "+2year"
2014-07-18 05:18:32
[root@localhost riqi]# date +"%Y-%m-%d %H:%M:%S" -d "-2year"
2010-07-18 05:18:36
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用shell将时间字符串与时间戳互转