A Techies' Blog

VBoxManage for controlling VirtualBox on the Command Line

The main tool for controlling VirtualBox is called VBoxManage. The VirtualBox manual has 27 pages describing all the available paramaters for using VirtualBox. The VirtualBox manual is a great resource to accompany this tutorial. [...]

You can use aliases to decrease the amount of typing you need to do to get
commands you commonly use. Examples of fairly popular aliases include (in
Bourne shell style, as in /bin/sh, bash, ksh, and zsh):

alias lf=”ls -FA”
alias ll=”ls -lA”
alias su=”su -m”

In csh or tcsh, these would be

alias lf ls -FA
alias ll ls -lA
alias su su -m

To remove an alias, you can usually use ‘unalias aliasname’. To list all
aliases, you can usually type just ‘alias’.

Want to know how many words, lines, or bytes are contained in a file? Type
“wc filename“.

To see how long it takes a command to run, type the word “time” before the
command name.

Want to use sed(1) to edit a file in place? Well, to replace every ‘e’ with an ‘o’, in a file named ‘foo’, you can do:

sed -i.bak s/e/o/g foo

And you’ll get a backup of the original in a file named ‘foo.bak’, but if you want no backup:

sed -i '' s/e/o/g foo

If you want to quickly check for duplicate package/port installations,
try the following pkg_info command.

pkg_info | sort | sed -e 's/-[0-9].*$//' | \
uniq -c | grep -v '^[[:space:]]*1'

You can ‘set autologout = 30‘ to have tcsh log you off automatically
if you leave the shell idle for more than 30 minutes.

To read a compressed file without having to first uncompress it, use
"zcat" or "zmore" to view it.

The default editor in FreeBSD is vi, which is efficient to use when you have
learned it, but somewhat user-unfriendly. To use ee (an easier but less
powerful editor) instead, set the environment variable EDITOR to /usr/bin/ee

Need to see the calendar for this month? Simply type “cal“. To see the
whole year, type “cal -y“.