提取每月的最后一个星期五和下一个星期日

问题描述

我想查找两个日期之间的一些信息（一个月的最后一个星期五和下一个星期日）。

现在，我将所有日期（格式为mm/dd/yy）添加到文件dates_file.in中，如下所示：

05/29/20,05/31/20
06/26/20,06/28/20
07/31/20,08/02/20

并像这样运行for循环

for dates in `cat dates_file.in`
do
date1=`echo $dates | cut -d',' -f1`
date2=`echo $dates | cut -d',' -f2`
xyz_cmd -start="$date1" -end="$date2" -report_parms
done

有没有一种方法可以使用calendar来获取日期或将日期导出到dates_file.in 文件？

OS是RHEL 6.5

解决方法

使用bash和GNU date：

# a function to return a positive number for "x % y"
# e.g.  `floorMod -1 7` outputs: 6
floorMod() { local num=$1 div=$2; echo $(( ((num % div) + div) % div )); }

formatDate() { local y=$1 m=$2 d=$3 delta=$4; date -d "$y-$m-$d $delta" "+%m/%d/%y"; }

year=2020
for month in {1..12}; do
    # get the last day of this month,and its day of the week
    read -r day dow < <(date -d "$year-$month-01 + 1 month - 1 day" "+%d %w")

    # decrement until we find Friday
    until ((dow == 5)); do
        ((day--))
        dow=$(floorMod $((dow - 1)) 7)
    done

    start=$(formatDate $year $month $day)
    end=$(formatDate $year $month $day "+2 days")
    echo "$start $end"
done

01/31/20 02/02/20
02/28/20 03/01/20
03/27/20 03/29/20
04/24/20 04/26/20
05/29/20 05/31/20
06/26/20 06/28/20
07/31/20 08/02/20
08/28/20 08/30/20
09/25/20 09/27/20
10/30/20 11/01/20
11/27/20 11/29/20
12/25/20 12/27/20

能否请您在此处使用cal进行尝试。

cat script.ksh
month="$1"
year="$2"
####To get current month's Friday.
cal "$month" "$year" 2>/dev/null |
tac |
awk '
NF>=6{
  print "current month last Friday is:"$(NF-1)" and Sunday is:"$NF
  exit
}
'

bash calendar