bash convert time to seconds code example

Example 1: shell script current time

date +'FORMAT'
 
### mm/dd/yyyy ###
date +'%m/%d/%Y'
 
## Time in 12 hr format ###
date +'%r'
 
## backup dir format ##
backup_dir=$(date +'%m/%d/%Y')
echo "Backup dir for today: /nas04/backups/${backup_dir}"

Example 2: bash get timestamp

# put current date as yyyy-mm-dd in $date
# -1 -> explicit current date, bash >=4.3 defaults to current time if not provided
# -2 -> start time for shell
printf -v date '%(%Y-%m-%d)T\n' -1 

# put current date as yyyy-mm-dd HH:MM:SS in $date
printf -v date '%(%Y-%m-%d %H:%M:%S)T\n' -1 

# to print directly remove -v flag, as such:
printf '%(%Y-%m-%d)T\n' -1
# -> current date printed to terminal