How to print dates between two dates in format %Y%m%d in shell script?

Using GNU date:

$ d=; n=0; until [ "$d" = "$enddate" ]; do ((n++)); d=$(date -d "$startdate + $n days" +%Y%m%d); echo $d; done2016051320160514

Or, spread over multiple lines:

startdate=20160512enddate=20160514d=n=0until [ "$d" = "$enddate" ]do      ((n++))    d=$(date -d "$startdate + $n days" +%Y%m%d)    echo $ddone

How it works

• d=; n=0

  Initialize variables.

• until [ "$d" = "$enddate" ]; do

  Start a loop that ends on enddate.

• ((n++))

  Increment the day counter.

• d=$(date -d "$startdate + $n days" +%Y%m%d)

  Compute the date for n days after startdate.

• echo $d

  Display the date.

• done

  Signal the end of the loop.

Another option is to use dateseq from dateutils (http://www.fresse.org/dateutils/#dateseq). -i changes the input format and -f changes the output format.

$ dateseq -i%Y%m%d -f%Y%m%d 20160512 20160514201605122016051320160514$ dateseq 2016-05-12 2016-05-142016-05-122016-05-132016-05-14

This should work on OSX, make sure your startdate is lesser than enddate, other wise try with epoch.

startdate=20160512enddate=20160514loop_date=$startdatelet j=0while [ "$loop_date" -ne "$enddate" ]; do        loop_date=`date   -j -v+${j}d  -f "%Y%m%d" "$startdate" +"%Y%m%d"`        echo $loop_date        let j=j+1done