#!/bin/sh 
printf -- 'Performing asynchronous action..'; 
DONE=0; 
printf -- '...................'; 
while [ $DONE -lt 10 ]; do 
 printf -- $DONE 
 sleep 1; 
 let DONE++ 
done; 
printf -- ' DONE!\n';

#!/bin/sh 
_=$(command -v docker); 
if [ "$?" != "0" ]; then 
 printf -- 'You don\'t seem to have Docker installed.\n'; 
 printf -- 'Get it: https://www.docker.com/community-edition\n'; 
 printf -- 'Exiting with code 127...\n'; 
 exit 127; 
fi; 
# ...

i=0 
sp='/-\|' 
n=${#sp} 
printf ' ' 
sleep 0.1 
while true; do 
    printf '\b%s' "${sp:i++%n:1}" 
    sleep 0.1 
done