Linux in a Nutshell, 6th Edition

Shell Programming

Command	Action
basename	Remove leading directory components from a path.
echo	Repeat command-line arguments on the output.
envsubst	Substitute the value of environment variables into strings.
expr	Perform arithmetic and comparisons.
mktemp	Generate temporary filename and create the file.
printf	Format and print command-line arguments.
sleep	Pause during processing.
test	Test a condition.