ShellはEpochを使って日付時間変換と計算のいくつかの小さな関数を行います。

コアコード

      date         ，          。

#     
function date2days {
  echo "$*" | awk '{
    z=int((14-$2)/12); y=$1+4800-z; m=$2+12*z-3;
    j=int((153*m+2)/5)+$3+y*365+int(y/4)-int(y/100)+int(y/400)-2472633;
    print j
  }'
}
date2days `echo "2010-08-18 18:59:19" | sed 's/-/ /g;s/:/ /g'`

#     
function days2date {
  echo "$1" | awk '{
    a=$1+2472632; b=int((4*a+3)/146097); c=int((-b*146097)/4)+a; 
    d=int((4*c+3)/1461); e=int((-1461*d)/4)+c; m=int((5*e+2)/153);
    dd=-int((153*m+2)/5)+e+1; mm=int(-m/10)*12+m+3; yy=b*100+d-4800+int(m/10);
    printf ("%4d-%02d-%02d
",yy,mm,dd)
  }'
}
days2date 14839

#     
function date2minutes {
  echo "$*" | awk '{
    z=int((14-$2)/12); y=$1+4800-z; m=$2+12*z-3;
    j=int((153*m+2)/5)+$3+y*365+int(y/4)-int(y/100)+int(y/400)-2472633;
    j=j*1440+$4*60+$5
    print j
  }'
}
date2minutes `echo "2010-08-18 18:59:19" | sed 's/-/ /g;s/:/ /g'`

#     
function minutes2date {
  echo "$1" | awk '{
    i=$1; nn=i%60; i=int(i/60); hh=i%24; dd=int(i/24); i=int(i/24);
    a=i+2472632; b=int((4*a+3)/146097); c=int((-b*146097)/4)+a; 
    d=int((4*c+3)/1461); e=int((-1461*d)/4)+c; m=int((5*e+2)/153);
    dd=-int((153*m+2)/5)+e+1; mm=int(-m/10)*12+m+3; yy=b*100+d-4800+int(m/10);
    printf ("%4d-%02d-%02d %02d:%02d
",yy,mm,dd,hh,nn)
  }'
}
minutes2date 21369299

#     
function date2seconds {
  echo "$*" | awk '{
    z=int((14-$2)/12); y=$1+4800-z; m=$2+12*z-3;
    j=int((153*m+2)/5)+$3+y*365+int(y/4)-int(y/100)+int(y/400)-2472633;
    j=j*86400+$4*3600+$5*60+$6
    print j
  }'
}
date2seconds `echo "2010-08-18 18:59:19" | sed 's/-/ /g;s/:/ /g'`

#     
function seconds2date {
  echo "$1" | awk '{
    i=$1; ss=i%60; i=int(i/60); nn=i%60; i=int(i/60); hh=i%24; dd=int(i/24); i=int(i/24);
    a=i+2472632; b=int((4*a+3)/146097); c=int((-b*146097)/4)+a; 
    d=int((4*c+3)/1461); e=int((-1461*d)/4)+c; m=int((5*e+2)/153);
    dd=-int((153*m+2)/5)+e+1; mm=int(-m/10)*12+m+3; yy=b*100+d-4800+int(m/10);
    printf ("%4d-%02d-%02d %02d:%02d:%02d
",yy,mm,dd,hh,nn,ss)
  }'
}
seconds2date 1282157959

#     
function date2milliseconds {
  echo "$*" | awk '{
    z=int((14-$2)/12); y=$1+4800-z; m=$2+12*z-3;
    j=int((153*m+2)/5)+$3+y*365+int(y/4)-int(y/100)+int(y/400)-2472633;
    j=j*86400+$4*3600+$5*60+$6
    printf ("%d%s
",j,$7)
  }'
}
date2milliseconds `echo "2010-08-18 18:59:19.073" | sed 's/-/ /g;s/:/ /g;s/\./ /g'`

#     
function milliseconds2date {
  echo "$1" | awk '{
    i=$1; ms=i%1000; i=int(i/1000); ss=i%60; i=int(i/60); nn=i%60; i=int(i/60); hh=i%24; dd=int(i/24); i=int(i/24);
    a=i+2472632; b=int((4*a+3)/146097); c=int((-b*146097)/4)+a; 
    d=int((4*c+3)/1461); e=int((-1461*d)/4)+c; m=int((5*e+2)/153);
    dd=-int((153*m+2)/5)+e+1; mm=int(-m/10)*12+m+3; yy=b*100+d-4800+int(m/10);
    printf ("%4d-%02d-%02d %02d:%02d:%02d.%03d
",yy,mm,dd,hh,nn,ss,ms)
  }'
}
milliseconds2date 1282157959073

アプリケーションの例:
今日のN日間以降の日付を計算します。

#!/bin/bash
function date2days {
  echo "$1 $2 $3" | awk '{
    z=int((14-$2)/12); y=$1+4800-z; m=$2+12*z-3;
    j=int((153*m+2)/5)+$3+y*365+int(y/4)-int(y/100)+int(y/400)-2472633;
    print j
  }'
}

function days2date {
  echo "$1" | awk '{
    a=$1+2472632; b=int((4*a+3)/146097); c=int((-b*146097)/4)+a; 
    d=int((4*c+3)/1461); e=int((-1461*d)/4)+c; m=int((5*e+2)/153);
    dd=-int((153*m+2)/5)+e+1; mm=int(-m/10)*12+m+3; yy=b*100+d-4800+int(m/10);
    printf ("%4d%02d%02d
",yy,mm,dd)
  }'
}

year=`date +%Y`; month=`date +%m`; day=`date +%d`
days=`date2days $year $month $day`
N=5
let days-=$N
days2date $days

ある日のN日間以降の日付を計算します。

#!/bin/bash
function date2days {
  echo "$1 $2 $3" | awk '{
    z=int((14-$2)/12); y=$1+4800-z; m=$2+12*z-3;
    j=int((153*m+2)/5)+$3+y*365+int(y/4)-int(y/100)+int(y/400)-2472633;
    print j
  }'
}

function days2date {
  echo "$1" | awk '{
    a=$1+2472632; b=int((4*a+3)/146097); c=int((-b*146097)/4)+a; 
    d=int((4*c+3)/1461); e=int((-1461*d)/4)+c; m=int((5*e+2)/153);
    dd=-int((153*m+2)/5)+e+1; mm=int(-m/10)*12+m+3; yy=b*100+d-4800+int(m/10);
    printf ("%4d%02d%02d
",yy,mm,dd)
  }'
}

year=2010; month=01; day=20
days=`date2days $year $month $day`
let days+=5
days2date $days

前の週の日付を全部計算します。

#!/bin/bash
function date2days {
  echo "$1 $2 $3" | awk '{
    z=int((14-$2)/12); y=$1+4800-z; m=$2+12*z-3;
    j=int((153*m+2)/5)+$3+y*365+int(y/4)-int(y/100)+int(y/400)-2472633;
    print j
  }'
}

function days2date {
  echo "$1" | awk '{
    a=$1+2472632; b=int((4*a+3)/146097); c=int((-b*146097)/4)+a; 
    d=int((4*c+3)/1461); e=int((-1461*d)/4)+c; m=int((5*e+2)/153);
    dd=-int((153*m+2)/5)+e+1; mm=int(-m/10)*12+m+3; yy=b*100+d-4800+int(m/10);
    printf ("%4d%02d%02d
",yy,mm,dd)
  }'
}

function date2week {
  echo "$1 $2 $3" | awk '{
    z=int((14-$2)/12); y=$1+4800-z; m=$2+12*z-3;
    dow=(int((153*m+2)/5)+$3+y*365+int(y/4)-int(y/100)+int(y/400)-2472629)%7;
    print dow
  }'
}

year=`date +%Y`; month=`date +%m`; day=`date +%d`
days=`date2days $year $month $day`
week=`date2week $year $month $day`
let dateEnd=$days-$week-1
let dateBegin=$dateEnd-6
for ((i=$dateBegin;i<=$dateEnd;i++)); do
  days2date $i
done

日付時間をミリ秒に変換

function date2milliseconds {
  echo "$*" | awk '{
    z=int((14-$2)/12); y=$1+4800-z; m=$2+12*z-3;
    j=int((153*m+2)/5)+$3+y*365+int(y/4)-int(y/100)+int(y/400)-2472633;
    j=j*86400+$4*3600+$5*60+$6
    print j$7
  }'
}

date2milliseconds `echo "2010-08-18 18:59:19.073" | /usr/xpg4/bin/awk -F'[:.-]+' '$1=$1'`

日付時間を秒に変換

function date2seconds {
  echo "$*" | awk '{
    z=int((14-$2)/12); y=$1+4800-z; m=$2+12*z-3;
    j=int((153*m+2)/5)+$3+y*365+int(y/4)-int(y/100)+int(y/400)-2472633;
    j=j*86400+$4*3600+$5*60+$6
    print j
  }'
}

date2seconds `echo "2010-07-21 00:00:00" | sed 's/-/ /g;s/:/ /g'`

数字が適法な日付かどうかを判断します。

function date2days {
  echo "$*" | awk '{
    z=int((14-$2)/12); y=$1+4800-z; m=$2+12*z-3;
    j=int((153*m+2)/5)+$3+y*365+int(y/4)-int(y/100)+int(y/400)-2472633;
    print j
  }'
}

function days2date {
  echo "$1" | awk '{
    a=$1+2472632; b=int((4*a+3)/146097); c=int((-b*146097)/4)+a; 
    d=int((4*c+3)/1461); e=int((-1461*d)/4)+c; m=int((5*e+2)/153);
    dd=-int((153*m+2)/5)+e+1; mm=int(-m/10)*12+m+3; yy=b*100+d-4800+int(m/10);
    printf ("%4d%02d%02d
",yy,mm,dd)
  }'
}

num1=20105050
num2=20101001
arg1=`echo "$num1" | sed -r 's/(....)(..)(..)/\1 \2 \3/g'`
arg2=`echo "$num2" | sed -r 's/(....)(..)(..)/\1 \2 \3/g'`
days1=`date2days $arg1`
date1=`days2date $days1`
days2=`date2days $arg2`
date2=`days2date $days2`
[ "$num1" -eq "$date1" ] && echo "$num1 is valid date" || echo "$num1 is invalid date"
[ "$num2" -eq "$date2" ] && echo "$num2 is valid date" || echo "$num2 is invalid date"

10分前の時間を計算します。

function date2minutes {
  echo "$*" | awk '{
    z=int((14-$2)/12); y=$1+4800-z; m=$2+12*z-3;
    j=int((153*m+2)/5)+$3+y*365+int(y/4)-int(y/100)+int(y/400)-2472633;
    j=j*1440+$4*60+$5
    print j
  }'
}
function minutes2date {
  echo "$1" | awk '{
    i=$1; nn=i%60; i=int(i/60); hh=i%24; dd=int(i/24); i=int(i/24);
    a=i+2472632; b=int((4*a+3)/146097); c=int((-b*146097)/4)+a; 
    d=int((4*c+3)/1461); e=int((-1461*d)/4)+c; m=int((5*e+2)/153);
    dd=-int((153*m+2)/5)+e+1; mm=int(-m/10)*12+m+3; yy=b*100+d-4800+int(m/10);
    printf ("%4d-%02d-%02d %02d:%02d
",yy,mm,dd,hh,nn)
  }'
}

now=`date "+%Y-%m-%d %H:%M" | sed 's/-/ /g;s/:/ /g'`
minutes=`date2minutes $now`
let minutes-=10
minutes2date $minutes

指定された日付と現在のシステムの日付の家の違いを計算します。

#!/bin/bash
function date2days {
  echo "$*" | awk '{
    z=int((14-$2)/12); y=$1+4800-z; m=$2+12*z-3;
    j=int((153*m+2)/5)+$3+y*365+int(y/4)-int(y/100)+int(y/400)-2472633;
    print j
  }'
}

echo "Enter your date:"
read input
InpuDays=$(date2days ${input:0:4} ${input:4:2} ${input:6:2})
SysDays=$(date2days `date +"%Y %m %d"`)
let result=$InpuDays-$SysDays
echo $result

#./test.sh
Enter your date:
20110605
25

先週の月曜日の日付

#!/bin/bash
function date2days {
  echo "$1 $2 $3" | awk '{
    z=int((14-$2)/12); y=$1+4800-z; m=$2+12*z-3;
    j=int((153*m+2)/5)+$3+y*365+int(y/4)-int(y/100)+int(y/400)-2472633;
    print j
  }'
}

function days2date {
  echo "$1" | awk '{
    a=$1+2472632; b=int((4*a+3)/146097); c=int((-b*146097)/4)+a; 
    d=int((4*c+3)/1461); e=int((-1461*d)/4)+c; m=int((5*e+2)/153);
    dd=-int((153*m+2)/5)+e+1; mm=int(-m/10)*12+m+3; yy=b*100+d-4800+int(m/10);
    printf ("%4d%02d%02d
",yy,mm,dd)
  }'
}

function date2week {
  echo "$1 $2 $3" | awk '{
    z=int((14-$2)/12); y=$1+4800-z; m=$2+12*z-3;
    dow=(int((153*m+2)/5)+$3+y*365+int(y/4)-int(y/100)+int(y/400)-2472629)%7;
    print dow
  }'
}

year=`date +%Y`; month=`date +%m`; day=`date +%d`
days=`date2days $year $month $day`
week=`date2week $year $month $day`
let date=$days-$week-7
days2date $date