Commands by virtualshock (5)

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Shows space used by each directory of the root filesystem excluding mountpoints/external filesystems (and sort the output)
Excludes other mountpoints with acavagni's "mountpoint" idea, but with -exec instead of piping to an xargs subshell. Then, calling "du" only once with -exec's "+" option. The first "\! -exec" acts as a test so only those who match are passed to the second "-exec" for du.

Use colordiff in side-by-side mode, and with automatic column widths.
Barely worth posting because it is so simple, but I use it literally all the time. I was always frustrated by the limitations that a non-gui environment imposes on diff'ing files. This fixes some of those limitations by colourising the output (you'll have to install colordiff, but it is just a wrapper for diff itself), using side-by-side mode for clearer presentation, and of course, the -W parameter, using tput to automatically insert you terminal width. Note that the double quotes aren't necessary if typed into terminal as-is. I included them for safety sake,

Finds all files from / on down over specified size.
Very useful for finding all files over a specified size, such as out of control log files chewing up all available disk space. Fedora Core x specific version.

Secure copy from one server to another without rsync and preserve users, etc
Source: http://unix.derkeiler.com/Newsgroups/comp.unix.shell/2008-04/msg00068.html

Password Generation
Produces secure passwords that satisfy most rules for secure passwords and can be customized for correct output as needed. See "man pwgen" for details.

Display the output of a command from the first line until the first instance of a regular expression.
Slightly simpler version of previous sed command that does the same thing. In this case, the output will stop at the command, and the entire command will be terminated as well, instead of proceeding through the whole file.

small CPU benchmark with PI, bc and time.
$ # 4 cores with 2500 pi digits $ CPUBENCH 4 2500 $. $ every core will use 100% cpu and you can see how fast they calculate it. $ if you do 50000 digitits and more it can take hours or days

Get AWS temporary credentials ready to export based on a MFA virtual appliance
You might want to secure your AWS operations requiring to use a MFA token. But then to use API or tools, you need to pass credentials generated with a MFA token. This commands asks you for the MFA code and retrieves these credentials using AWS Cli. To print the exports, you can use: `awk '{ print "export AWS_ACCESS_KEY_ID=\"" $1 "\"\n" "export AWS_SECRET_ACCESS_KEY=\"" $2 "\"\n" "export AWS_SESSION_TOKEN=\"" $3 "\"" }'` You must adapt the command line to include: * $MFA_IDis ARN of the virtual MFA or serial number of the physical one * TTL for the credentials

suspend to ram without root
$dbus-send --system --print-reply --dest="org.freedesktop.UPower" /org/freedesktop/UPower org.freedesktop.UPower.Suspend

View all file operator expressions for any file, test, stat
Applies each file operator using the built-in test. $ testt /home/askapache/.sq /home/askapache/.sq -a True - file exists. -d True - file is a directory. -e True - file exists. -r True - file is readable by you. -s True - file exists and is not empty. -w True - the file is writable by you. -x True - the file is executable by you. -O True - the file is effectively owned by you. -G True - the file is effectively owned by your group. -N True - the file has been modified since it was last read. Full Function: testt () { local dp; until [ -z "${1:-}" ]; do dp="$1"; [[ ! -a "$1" ]] && dp="$PWD/$dp"; command ls -w $((${COLUMNS:-80}-20)) -lA --color=tty -d "$dp"; [[ -d "$dp" ]] && find "$dp" -mount -depth -wholename "$dp" -printf '%.5m %10M %#15s %#9u %-9g %#5U %-5G %Am/%Ad/%AY %Cm/%Cd/%CY %Tm/%Td/%TY [%Y] %p\n' -a -quit 2> /dev/null; for f in a b c d e f g h L k p r s S t u w x O G N; do test -$f "$dp" && help test | sed "/-$f F/!d" | sed -e 's#^[\t ]*-\([a-zA-Z]\{1\}\) F[A-Z]*[\t ]* True if#-\1 "'$dp'" #g'; done; shift; done }


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