Learn Linux Shell Scripting - Fundamentals of Bash 4.4

at

The at command is used mostly for ad hoc scheduling. The syntax for at is very close to our natural language. This is easiest explained with an example, as follows:

reader@ubuntu:~/scripts/chapter_14$ dateSat Nov 24 11:50:12 UTC 2018reader@ubuntu:~/scripts/chapter_14$ at 11:51warning: commands will be executed using /bin/shat> wall "Hello readers!"at> <EOT>job 6 at Sat Nov 24 11:51:00 2018reader@ubuntu:~/scripts/chapter_14$ dateSat Nov 24 11:50:31 UTC 2018Broadcast message from reader@ubuntu (somewhere) (Sat Nov 24 11:51:00 2018):Hello readers!reader@ubuntu:~/scripts/chapter_14$ dateSat Nov 24 11:51:02 UTC 2018

In essence, you're telling the system: at <timestamp>, do something. When you enter the at 11:51 command, you will be placed in ...