Append contents of all matching files to sum.log
cat *.log >> sum.log
Overwrite sum.log with contents of all matching files
cat *.log > sum.log
Get full path of a file (file does not need to exist)
readlink -f file.txt
Repeat a command n times
for run in {1..10}; do command; done
Convert timestamp to human readable date
date -d @641288145
Shorten prompt in current terminal
PS1='\u:\W\$ '