- Recursive touch
Touch a bunch of directories recursively. All the directories and their contents (To re-stamp time on all files)$ find DIR | xargs touch
- Redirecting Standard Error
Redirecting errors when compiling,the number 2 represents the standard error output stream,
1 represent standard output.$ make > output.txt 2>&1
- Command Substitution
To use command substitution, enclose any command that generates output to standard output
inside parentheses and precede the opening parenthesis with a dollar sign, $(command).
It is handy for using the output of one command as an argument to another command.$ rpm -ql $(rpm -qa | grep httpd)
- Using for Loops from the Command Line
For small loops it can be a great time saver. Example: A simple loop to make a
backup copy of all the files in a directory:$ for file in * ; do cp $file $file.bak; done
