Contents

Startup & Shutdown

• Shutdown the machine immediately and reboot

  shutdown -r now

• Shutdown the machine and immediately power off (for ATX hardware, you will need to install and enable the apm(8) support in kernel: see ?How to poweroff at shutdown for details)

  shutdown -p now

• Shutdown the machine and halt afterwards (but keep the power on)

  shutdown -h now

File & Directory Operations

• Find out what directory you are in

  pwd

• List contents of current working directory

  ls

• Copy a file to a new file with a different name

  cp foobar.txt barfoo.txt

• Remove a file (delete it)

  rm foobar.txt

• Remove an ""empty"" directory.

  rmdir mydir

• Recursively remove a directory (be careful with this, if you mess up, you can easily wipe out your whole system). This will remove the directory and all the files and subdirectories it contains, provided you have permissions.

  rm -rf mydir

Using Archives

• Create a ""tar"" archive with the contents of a directory displaying each file and directory as tar runs verbosely.

  tar cvf my_archive.tar some_directory

The same using pax:

pax -w -v -f my_archive.tar some_directory

• Extract a ""tar"" archive to the current directory displaying each file and directory as tar runs verbosely.

  tar xvf my_archive.tar

The same using pax:

pax -r -v -f my_archive.tar

• Compress a file with gzip using maximum (slowest) compression

  gzip -9 foobar.txt

• Compress a file with bzip2 using maximum (slowest) compression. Bzip generally compresses files better at the cost of greater time during the compression phase. The archives it creates generally de-compress at the same speed as gzip.

  bzip2 -9 foobar.txt

User Operations

• Add a new user and create their home directory

  useradd -m jsmith

• Change a user's default shell

  chsh -s /path/newshell jsmith

or

chpass -s /bin/ksh jsmith

Package Operations (pkgsrc)

• Add a binary package

  pkg_add my_binary_package.tgz

• List all (installed) packages

  pkg_info

• List all files that are part of a directory

  pkg_info -L the_package_name

• Delete a package

  pkg_delete the_package_name

• Create a binary package file from an already installed package (this requires the pkg_tarup tool from pkgsrc which lives under the pkgtools subdirectory.)

  pkg_tarup the_package_name

Advanced Command Line Recipes

• Create a binary package for every single installed package on the system and place them all in the current directory.

  for pkg in pkg_info -e "*" | sort; do echo "Packaging $pkg"; pkg_tarup -d . $pkg 1>/dev/null; done