[root@localhost shell]# date
Tue Jul 5 04:58:08 CST 2011
[root@localhost shell]# date 显示系统当前日期
Tue Jul 5 04:58:15 CST 2011
[root@localhost shell]# date 2011-07-06
date: invalid date `2011-07-06'
[root@localhost shell]# date -s 2011-07-06 修改当前日期
Wed Jul 6 00:00:00 CST 2011
[root@localhost shell]# date 显示修改后的日期
Wed Jul 6 00:00:02 CST 2011
[root@localhost shell]# date -d "+4 day" 显示4天后的日期
Sun Jul 10 00:00:27 CST 2011
[root@localhost shell]# date -d "+4 day" +%y%m%d 格式化显示
110710
[root@localhost shell]# date -d "+4 day" +%Y%m%d 格式化显示
20110710
[root@localhost shell]# date -d "-4 day" +%Y%m%d 4天前
20110702
[root@localhost shell]# date -d "yesterday" +%Y%m%d 显示昨天
20110705
[root@localhost shell]# date -d "tomorrow" +%Y%m%d 显示明天
20110707
[root@localhost shell]# date -d "2 days ago" +%Y%m%d 显示2天前
20110704
