날짜와 시간 처리

2020-01-15

시간 설정

$ date -s "2020-02-02 04:00:20"

날짜 포맷 출력(기본 포맷)

mm/dd/yy형식으로 날짜 출력

date +"%D"

날짜 포맷 출력(지정 포맷)

yyyy-mm-dd 형식의 날짜 출력

date "+%Y-%m-%d"
echo date # 2020-01-14

시간 출력(기본 포맷)

hh-mm-ss 형식의 시간 출력

date +"%T" # 04:09:51

시간 출력(12시간 기준)

date +"%r" # 04:09:51 AM

날짜와 시간 출력(기본 포맷)

now=$(date)
echo $no # 2020년 1월 15일 수요일 05시 19분 36초 MSK

날짜와 시간 출력(지정 포맷)

yyyy-mm-dd_hh-mm-ss 형식으로 출력

echo $(date +%F_%H-%M-%S) # 2020-01-15_05-12-24

시간 조건 분기(12시간 기준)

쉘 코드로 오전(AM), 오후(PM)에 대한 조건 분기는 다음과 같습니다.

h=$(date +%H)
if (( h < 12)); then
    echo YES # AM
else
    echo NO  # PM
fi

출력결과

YES

[첨부] Date 포맷 코드 목록

FORMAT code	Description
%%	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
%q	quarter of year (1..4)
%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)

출처 : https://www.cyberciti.biz/faq/linux-unix-formatting-dates-for-display/

[첨부] GNU/date 포맷코드

FORMAT controls the output. It can be the combination of any one of the following:

%FORMAT String	Description
%%	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., 21)
%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 ( 0..23)
%l	hour ( 1..12)
%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 timezone (e.g., -0400)
%:z	+hh:mm numeric timezone (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)

출처 : https://www.cyberciti.biz/faq/linux-unix-formatting-dates-for-display/

[첨부] BSD/date 커맨드(맥OS, FreeBSD)

포맷 코드	설명
%a	is replaced by national representation of the abbreviated weekday name.
%B	is replaced by national representation of the full month name.
%b	is replaced by national representation of the abbreviated month name.
%C	is replaced by (year / 100) as decimal number; single digits are preceded by a zero.
%c	is replaced by national representation of time and date.
%D	is equivalent to “%m/%d/%y”.
%d	is replaced by the day of the month as a decimal number (01-31).
%E* %O*	POSIX locale extensions. The sequences %Ec %EC %Ex %EX %Ey %EY %Od %Oe %OH %OI %Om %OM %OS %Ou %OU %OV %Ow %OW %Oy are supposed to provide alternate representations. Additionally %OB implemented to represent alternative months names (used standalone, without day mentioned).
%e	is replaced by the day of the month as a decimal number (1-31); single digits are preceded by a blank.
%G	is replaced by a year as a decimal number with century. This year is the one that contains the greater part of the week (Monday as the first day of the week).
%g	is replaced by the same year as in “%G”, but as a decimal number without century (00-99).
%H	is replaced by the hour (24-hour clock) as a decimal number (00-23).
%h	the same as %b.
%I	is replaced by the hour (12-hour clock) as a decimal number (01-12).
%j	is replaced by the day of the year as a decimal number (001-366).
%k	is replaced by the hour (24-hour clock) as a decimal number (0-23); single digits are preceded by a blank.
%l	is replaced by the hour (12-hour clock) as a decimal number (1-12); single digits are preceded by a blank.
%M	is replaced by the minute as a decimal number (00-59).
%m	is replaced by the month as a decimal number (01-12).
%n	is replaced by a newline.
%O*	the same as %E*.
%p	is replaced by national representation of either “ante meridiem” (a.m.) or “post meridiem” (p.m.) as appropriate.
%R	is equivalent to “%H:%M”.
%r	is equivalent to “%I:%M:%S %p”.
%S	is replaced by the second as a decimal number (00-60).
%s	is replaced by the number of seconds since the Epoch, UTC (see mktime(3)).
%T	is equivalent to “%H:%M:%S”.
%t	is replaced by a tab.
%U	is replaced by the week number of the year (Sunday as the first day of the week) as a decimal number (00-53).
%u	is replaced by the weekday (Monday as the first day of the week) as a decimal number (1-7).
%V	is replaced by the week number of the year (Monday as the first day of the week) as a decimal number (01-53). If the week containing January 1 has four or more days in the new year, then it is week 1; otherwise it is the last week of the previous year, and the next week is week 1.
%v	is equivalent to “%e-%b-%Y”.
%W	is replaced by the week number of the year (Monday as the first day of the week) as a decimal number (00-53).
%w	is replaced by the weekday (Sunday as the first day of the week) as a decimal number (0-6).
%X	is replaced by national representation of the time.
%x	is replaced by national representation of the date.
%Y	is replaced by the year with century as a decimal number.
%y	is replaced by the year without century as a decimal number (00-99).
%Z	is replaced by the time zone name.
%z	is replaced by the time zone offset from UTC; a leading plus sign stands for east of UTC, a minus sign for west of UTC, hours and minutes follow with two digits each and no delimiter between them (common form for RFC 822 date headers).
%+	is replaced by national representation of the date and time (the format is similar to that produced by date(1)).
%-*	GNU libc extension. Do not do any padding when performing numerical outputs.
%_*	GNU libc extension. Explicitly specify space for padding.
%0*	GNU libc extension. Explicitly specify zero for padding.
%%	is replaced by %.