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Full Discussion: Bash Display First Friday of the next month
Operating Systems Linux Bash Display First Friday of the next month Post 303009890 by Don Cragun on Thursday 21st of December 2017 03:23:22 PM
Old 12-21-2017
You haven't told us what version of bash you're using...

The following works at least with ksh version 93u+ and later versions. I believe it will also work unchanged with a recent release of bash:
Code:
if [ $# -eq 2 ]
then	MONTH=$1
	YEAR=$2
else	read MONTH YEAR <<-EOF
		$(printf '%(%m %Y)T')
EOF
fi

for((i = 1; i <= 12; i++))
do
	read MONTH YEAR <<-EOF
		$(printf '%(%m %Y)T' "$MONTH/01/$YEAR next month")
EOF
	DOW1ST=$(printf '%(%u)T' "$MONTH/01/$YEAR")
	if [ $DOW1ST -eq 5 ]
	then	FIRSTFRIDAY=01
	else	FIRSTFRIDAY=0$(((13 - DOW1ST) % 7))
		[ $FIRSTFRIDAY = "00" ] && FIRSTFRIDAY=07
	fi
	printf '%s/%s/%s\n' "$MONTH" "$FIRSTFRIDAY" "$YEAR"
done

If you invoke it without arguments it will give you the 1st Friday of each month for the next year. For instance, when I run it today, it prints:
Code:
01/05/2018
02/02/2018
03/02/2018
04/06/2018
05/04/2018
06/01/2018
07/06/2018
08/03/2018
09/07/2018
10/05/2018
11/02/2018
12/07/2018

If you invoke it with two arguments specifying a month and a year, it will give you the 1st Fridays for the year following that month and year. For example:
Code:
ksh ./tester 6 2016

prints:
Code:
07/01/2016
08/05/2016
09/02/2016
10/07/2016
11/04/2016
12/02/2016
01/06/2017
02/03/2017
03/03/2017
04/07/2017
05/05/2017
06/02/2017

If that doesn't work with your version of bash, the following should come close to working for you, but is totally untested (since I don't have access to the GNU date utility):
Code:
if [ $# -eq 2 ]
then	MONTH=$1
	YEAR=$2
else	read MONTH YEAR <<-EOF
		$(date '+%m %Y')
EOF
fi

for((i = 1; i <= 12; i++))
do
	read MONTH YEAR <<-EOF
		$(date -d "$MONTH/01/$YEAR next month" '+%m %Y')
EOF
	DOW1ST=$(date -d "$MONTH/01/$YEAR" +%u)
	if [ $DOW1ST -eq 5 ]
	then	FIRSTFRIDAY=01
	else	FIRSTFRIDAY=0$(((13 - DOW1ST) % 7))
		[ $FIRSTFRIDAY = "00" ] && FIRSTFRIDAY=07
	fi
	printf '%s/%s/%s\n' "$MONTH" "$FIRSTFRIDAY" "$YEAR"
done

I assume that you'll be able to simplify either of these scripts to get what you want.
 

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