Shell Programming and Scripting

$ now=$(date +%s)
$ a_6am_cross=$(date -d" 6:00:01 AM" +%s)
$ if [ $now -eq $a_6am_cross ]; then echo "Its 6:00:01 exiting your exit code goes here"; else echo "Keep looping";fi

date: illegal option -- d
date: illegal option --
date: illegal option -- 6
date: illegal option -- :
date: illegal option -- 0
date: illegal option -- 0
date: illegal option -- :
date: illegal option -- 0
date: illegal option -- 1
date: illegal option --
date: illegal option -- A
date: illegal option -- M

a_6am_cross=$(date -d " 6:00:01 AM" +%s)

date +%s

%s

date -d " 6:00:01 AM" +%s

date: illegal option -- d
usage:  date [-u] mmddHHMM[[cc]yy][.SS]
        date [-u] [+format]
        date -a [-]sss[.fff]

man watch

mkfifo goodfiles     
while [ $(date +%H) -ge 19 -o $(date +%H) -lt 6 ]
  do  awk '{print $2 "\tYES"}' goodfiles & LC_ALL=C stat -c"%G %n" $(cut -d" " -f2 files.txt) 2>&1 1>goodfiles | awk -F\' '{print $2 "\tNO"} END {if (NR>0) exit 20}'; 
      sleep 900
  done

file    YES
file~    YES
file1    YES
file1~    YES
file2    YES
file2~    YES
file3    YES
file3~    YES
file4    YES
file4~    YES
file6    NO
file5    NO