Linux date输出取前一天,Shell中获取取今天、明天、昨天和多天前日期

1. 获取今天日期
   date -d now +%Y-%m-%d 或者 $ date +%F
2. 获取明天日期
   date -d next-day +%Y-%m-%d
date -d tomorrow +%Y-%m-%d
3. 获取昨天日期
   date -d yesterday +%Y-%m-%d 或date -d last-day +%Y-%m-%d 或者date -d "1 days ago" +%Y-%m-%d
   "n days ago" 表示n天前的那一天
4. 获取取30天前的日期
   date -d "30 days ago" +%Y-%m-%d
5. 使用负数以得到相反的日期
   date -d 'dec 14 -2 weeks' +%F #相对于dec 14这个日期的两周前的日期
   date -d '-100 days' +%F #100天以前的日期
   date -d '50 days' +%F #50天后的日期

扩展：

date -d next-month +%F #下个月今天日期

date -d last-month +%F #上个月今天日期

date -d next-year +%Y #明年日期

date -d '2 weeks' +%F #获取两星期以后的日期

date使用帮助说明

date --help
Usage: date [OPTION]... [+FORMAT]
  or:  date [-u|--utc|--universal] [MMDDhhmm[[CC]YY][.ss]]
Display the current time in the given FORMAT, or set the system date.
 
Mandatory arguments to long options are mandatory for short options too.
  -d, --date=STRING         display time described by STRING, not 'now'
  -f, --file=DATEFILE       like --date once for each line of DATEFILE
  -I[TIMESPEC], --iso-8601[=TIMESPEC]  output date/time in ISO 8601 format.
                            TIMESPEC='date' for date only (the default),
                            'hours', 'minutes', 'seconds', or 'ns' for date
                            and time to the indicated precision.
  -r, --reference=FILE      display the last modification time of FILE
  -R, --rfc-2822            output date and time in RFC 2822 format.
                            Example: Mon, 07 Aug 2006 12:34:56 -0600
      --rfc-3339=TIMESPEC   output date and time in RFC 3339 format.
                            TIMESPEC='date', 'seconds', or 'ns' for
                            date and time to the indicated precision.
                            Date and time components are separated by
                            a single space: 2006-08-07 12:34:56-06:00
  -s, --set=STRING          set time described by STRING
  -u, --utc, --universal    print or set Coordinated Universal Time (UTC)
      --help     display this help and exit
      --version  output version information and exit
 
FORMAT controls the output.  Interpreted sequences are:
 
  %%   a literal %
  %a   locale's abbreviated weekday name (e.g., Sun)
  %A   locale's full weekday name (e.g., Sunday)
  %b   locale's abbreviated month name (e.g., Jan)
  %B   locale's full month name (e.g., January)
  %c   locale's date and time (e.g., Thu Mar  3 23:05:25 2005)
  %C   century; like %Y, except omit last two digits (e.g., 20)
  %d   day of month (e.g., 01)
  %D   date; same as %m/%d/%y
  %e   day of month, space padded; same as %_d
  %F   full date; same as %Y-%m-%d
  %g   last two digits of year of ISO week number (see %G)
  %G   year of ISO week number (see %V); normally useful only with %V
  %h   same as %b
  %H   hour (00..23)
  %I   hour (01..12)
  %j   day of year (001..366)
  %k   hour, space padded ( 0..23); same as %_H
  %l   hour, space padded ( 1..12); same as %_I
  %m   month (01..12)
  %M   minute (00..59)
  %n   a newline
  %N   nanoseconds (000000000..999999999)
  %p   locale's equivalent of either AM or PM; blank if not known
  %P   like %p, but lower case
  %r   locale's 12-hour clock time (e.g., 11:11:04 PM)
  %R   24-hour hour and minute; same as %H:%M
  %s   seconds since 1970-01-01 00:00:00 UTC
  %S   second (00..60)
  %t   a tab
  %T   time; same as %H:%M:%S
  %u   day of week (1..7); 1 is Monday
  %U   week number of year, with Sunday as first day of week (00..53)
  %V   ISO week number, with Monday as first day of week (01..53)
  %w   day of week (0..6); 0 is Sunday
  %W   week number of year, with Monday as first day of week (00..53)
  %x   locale's date representation (e.g., 12/31/99)
  %X   locale's time representation (e.g., 23:13:48)
  %y   last two digits of year (00..99)
  %Y   year
  %z   +hhmm numeric time zone (e.g., -0400)
  %:z  +hh:mm numeric time zone (e.g., -04:00)
  %::z  +hh:mm:ss numeric time zone (e.g., -04:00:00)
  %:::z  numeric time zone with : to necessary precision (e.g., -04, +05:30)
  %Z   alphabetic time zone abbreviation (e.g., EDT)
 
By default, date pads numeric fields with zeroes.
The following optional flags may follow '%':
 
  -  (hyphen) do not pad the field
  _  (underscore) pad with spaces
  0  (zero) pad with zeros
  ^  use upper case if possible
  #  use opposite case if possible
 
After any flags comes an optional field width, as a decimal number;
then an optional modifier, which is either
E to use the locale's alternate representations if available, or
O to use the locale's alternate numeric symbols if available.
 
Examples:
Convert seconds since the epoch (1970-01-01 UTC) to a date
  $ date --date='@2147483647'
 
Show the time on the west coast of the US (use tzselect(1) to find TZ)
  $ TZ='America/Los_Angeles' date
 
Show the local time for 9AM next Friday on the west coast of the US
  $ date --date='TZ="America/Los_Angeles" 09:00 next Fri'
 
GNU coreutils online help: <http://www.gnu.org/software/coreutils/>
For complete documentation, run: info coreutils 'date invocation'