Brad Conte » Three Tips for the Linux Terminal

The power of Linux lies in the tools it uses. If you spend a lot of time in a terminal, you likely value anything that makes using it smoother. Here are a few tips to help make the terminal experience as smooth as possible. These tips are all shell-independent.

Change directories with the directory stack
The Bash shell (as well as others, like Zsh) have a built-in “back” feature for navigating directories. The built-in “pushd” command will put your current working path at the top of a shell-maintained stack and allow you to change to another directory. To go back to the saved path you can use “popd”.

Example:
user@host : /some/long/path/you/don’t/want/to/retype$ pushd /some/other/path/ /some/long/path/you/don’t/want/to/retype user@host : /some/other/path/$ [do stuff] user@host : /some/other/path/$ popd /some/big/long/directory/you/don’t/want/to/retype user@host : /some/long/path/you/don’t/want/to/retype$
Since “pushd” stores the directories in a stack, you can push multiple directories onto the stack and later pop them off in the reverse order you pushed them. It’s basically the standard “cd” only with a “back” feature. Speaking of which, the command “$ cd -” will always take you back to the previous directory you were in.
Interact with the X clipboard
Before I discovered “xclip”, one of the most annoying things about being in a terminal was my lack of access to the X clipboard. Most shells (all the ones I’ve come across) have a simple means of pasting text into the terminal, but not all have an elegant means of getting text out of the terminal. Yes, highlight-and-middle-click is often an option, but it’s a) not always feasible, and b) not always convenient. Remember, this is the terminal, you don’t necessarily want to be using your mouse. “xclip” removes the annoyance of using the X clipboard.

xclip can read and store to the clipboard from the standard input. As well, it can output the current contents of the clipboard. Since xclip can manipulate multiple clipboard buffers, the argument “-selection c” must be used to select the standard X clipboard. The “-i” and “-o” arguments tell xclip whether you are inputting or outputting clipboard contents, respectively.

Example:
$ pwd /some/long/path/you/don’t/want/to/retype $ ls /some/path | xclip -selection c -i
You may now paste (standard Ctrl-v, or right-click -> paste) the directory listing where ever you choose. Another example:
xclip -selection c -o | cat >> /some/file
This will concatenate the contents of the clipboard to “/some/file”.

If you only use yourself using xclip to manage the X clipboard, you might want to consider aliasing “xclip” to “xclip -selection c” to make it simpler to type. Or you could take it one step further and alias “xcopy” to “xclip -selection c -i” and “xpaste” to “xclip -selection c -o”, or something similar.
Use “head” and “tail” more powerfully
You probably know how to use “head” to extract the first N lines from a file and “tail” to extract the last N lines of a file. While this is useful, it’s often just as useful to extract the complement of those selections, namely, everything except the first N lines or everything except the last N lines.

Thankfully, “head” and “tail” are powerful enough to accommodate those needs. “head” allows you to extract either a finite quantity of text from the top or everything but a finite quantity of text from the bottom, and “tail” allows you to extract a finite quantity of text from the bottom or everything but a finite quantity of text from the top.

• head -n N — by default outputs the first N lines. Using -N outputs all but the last N lines.

• tail -n N — by default outputs the last N lines. Using +N outputs lines starting on the Nth.

Example:
/tmp $ cat example 1 2 3 4 5 /tmp $ head -n 2 example 1 2 /tmp $ tail -n 2 example 4 5 /tmp $ head -n -2 example 1 2 3 /tmp $ tail -n +3 example 3 4 5
Note that tail’s complement mode requires you to specify the first line number to include in the output. Thus if you want all but the top N lines, actually specify N+1.