Learn the basic syntax of the shell and play with linux

01. Get the current time, year, month, day, hour, minute, second

now=$(date +%Y%m%d%H%M%S)
echo "$now"

The output is: 20181202222727

02. Several uses of date in scripts

date +%Y print year in 4 digit format
date +%y print year in 2 digit format
date +%m month
date +%d date date +
%H hour date
+%M minute
date +%S second
date +% w weekday, 0 for Sunday

03. Other usages, get the time before the current time

 If you want to learn automated testing, here I recommend a set of videos for you. This video can be said to be the number one automated testing tutorial on the entire network at station B. At the same time, the number of people online has reached 1,000, and there are notes to collect and share with you. Dashen Technical Exchange: 798478386   

[Updated] The most detailed collection of practical tutorials for automated testing of Python interfaces taught by station B (the latest version of actual combat)_哔哩哔哩_bilibili [Updated] The most detailed collection of practical tutorials for automated testing of Python interfaces taught by station B (actual combat) The latest version) has a total of 200 videos, including: 1. Why should interface automation be done in interface automation, 2. The overall view of request in interface automation, 3. Interface combat in interface automation, etc. UP hosts more exciting videos, please pay attention to UP account . https://www.bilibili.com/video/BV17p4y1B77x/?spm_id_from=333.337.search-card.all.click

The first way of writing:

Get the number in front of day, hour, minute, second day: negative number is the previous few days, positive number is the next few days, minutes and seconds are the same
date -d "-1 hour" +%H 1 hour before
date -d "- 1 min" +%M 1 minute before
date -d "-1 second" +%S 1 second before

date -d "-n day" +%d Get the date of the previous n days
date -d "n days" +%Y%m%d Get the time after n days

date -d "3 years ago" +%Y%m%d Get the time 3 years ago
date -d "3 years" +%Y%m%d Get the time 3 years later

date -d "3 month ago" +%m get 3 months ago
date -d "3 month" +%Y%m get 3 months later

The second way of writing:

date -d "n days ago" +%d Get the date n days ago
date -d "-n days ago" +%Y%m%d Get the date n days later

date -d "n month ago" +%d Get the date n months ago
date -d "-n month ago" +%Y%m%d Get the date n months later

date -d "n month ago" +%d Get the date n years ago
date -d "-n month ago" +%Y%m%d Get the date n years later

The third way of writing:

date +%Y%m%d --date="-n day" get the date n days ago
date +%Y%m%d --date="-n day" get the date n days later

date +%Y%m%d --date="n month ago" Get the date n months ago
date +%Y%m%d --date="-n month ago" Get the date n months later

date +%Y%m%d --date="n years ago" Get the date n years ago
date +%Y%m%d --date="-n years ago" Get the date n years later