ls /etc/acpi/
acpi_handler.sh  events

ls -al /etc/acpi/events/
total 20
drwxr-xr-x 2 root root 4096 May 21 22:58 .
drwxr-xr-x 3 root root 4096 May 19 10:28 ..
-rw-r--r-- 1 root root   49 May 21 18:40 LID
-rw-r--r-- 1 root root  635 Aug 21  2019 default
-rwxr-xr-x 1 root root  546 May 21 22:58 sleep.sh

cat /etc/acpi/events/LID 
event=button/lid
action=/etc/acpi/sleep.sh "%e" 

cat /etc/acpi/sleep.sh
echo -n "mem" > /sys/power/state

cat /etc/acpi/events/default 
# This is the ACPID default configuration, it takes all
# events and passes them to /etc/acpi/default.sh for further
# processing.

# event keeps a regular expression matching the event. To get
# power events only, just use something like "event=button power.*"
# to catch it.
# action keeps the command to be executed after an event occurs
# In case of the power event above, your entry may look this way:
#event=button power.*
#action=/sbin/init 0

# Optionally you can specify the placeholder %e. It will pass
# through the whole kernel event message to the program you've
# specified.

event=.*
action=/etc/acpi/acpi_handler.sh %e

ls -al /etc/acpi/events/
total 20
drwxr-xr-x 2 root root 4096 May 21 22:58 .
drwxr-xr-x 3 root root 4096 May 19 10:28 ..
-rw-r--r-- 1 root root   49 May 21 18:40 LID
-rw-r--r-- 1 root root  635 Aug 21  2019 default
-rwxr-xr-x 1 root root  546 May 21 22:58 sleep.sh

cat /etc/acpi/sleep.sh
echo -n "mem" > /sys/power/state

cat /etc/acpi/events/LID 
event=button/lid*
action=/etc/acpi/sleep.sh "%e"