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Terminal - All commands - 12,323 results
for a in bzip2 lzma gzip;do echo -n>$a;for b in $(seq 0 256);do dd if=/dev/zero of=$b.zero bs=$b count=1;c=$(date +%s%N);$a $b.zero;d=$(date +%s%N);total=$(echo $d-$c|bc);echo $total>>$a;rm $b.zero *.bz2 *.lzma *.gz;done;done
2009-10-20 01:00:51
User: matthewbauer
Functions: bzip2 date dd echo seq
3

See: http://imgur.com/JgjK2.png for example.

Do some serious benchmarking from the commandline. This will write to a file with the time it took to compress n bytes to the file (increasing by 1).

Run:

gnuplot -persist <(echo "plot 'lzma' with lines, 'gzip' with lines, 'bzip2' with lines")

To see it in graph form.

cat private-file | gpg2 --encrypt --armor --recipient "Disposable Key" | mailx -s "Email Subject" [email protected]
2009-10-19 20:38:37
User: slashdot
Functions: cat mailx
2

This is a quick and easy way of encrypting files in a datastream, without ever really creating an output file from gpg. Useful with cron also, when file(s) have to be sent based on a set schedule.

sed -ne '/^Package: \(.*\)/{s//\1/;h;};/^Installed-Size: \(.*\)/{s//\1/;G;s/\n/ /;p;}' /var/lib/dpkg/status | sort -rn
2009-10-19 19:01:17
User: arcege
Functions: sed sort
-2

Use the hold space to preserve lines until data is needed.

awk '{if (NR == 3) print}' <file>
2009-10-19 15:58:09
User: yooreck
Functions: awk
-5

I don't know if it's better but works fine :)

perl -ne '$pkg=$1 if m/^Package: (.*)/; print "$1\t$pkg\n" if m/^Installed-Size: (.*)/;' < /var/lib/dpkg/status | sort -rn | less
2009-10-19 12:55:59
User: hfs
Functions: perl sort
0

List packages and their disk usage in decreasing order. This uses the "Installed-Size" from the package metadata. It may differ from the actual used space, because e.g. data files (think of databases) or log files may take additional space.

rsync -rvtW --progress --include='*.wmv' --include='*.mpg' --exclude='*.*' <sourcedir> <destdir>
2009-10-19 10:38:11
Functions: rsync
Tags: rsync
1

Copying only wmv and mpg files recursively from to

uuencode -m $1 /dev/stdout | sed '1d' | sed '$d' | tr -d '\n' | xclip -selection clipboard
2009-10-19 09:03:09
User: caliburning
Functions: sed tr uuencode
Tags: xclip uuencode
1

I use it for embedding images in CSS for Stylish, the Firefox addon.

Thought it might be useful to others.

sed -n '/^function h\(\)/,/^}/p' script.sh
2009-10-19 07:55:35
User: haivu
Functions: sed
Tags: bash sed
8

I often need to extract a function from a bash script and this command will do it.

geoip(){curl -s "http://www.geody.com/geoip.php?ip=${1}" | sed '/^IP:/!d;s/<[^>][^>]*>//g' ;}
echo start > battery.txt; watch -n 60 'date >> battery.txt ; acpi -b >> battery.txt'
2009-10-19 05:28:15
User: m33600
Functions: acpi echo watch
1

This time I added a print to reemaining energy, every minute, time stamped.

The example shown here is complete and point to large discrepancies as time passes, converging to accuracy near the end.

for i in $(netstat --inet -n|grep ESTA|awk '{print $5}'|cut -d: -f1);do geoiplookup $i;done
2009-10-18 20:41:47
Functions: awk cut grep netstat
3

Sample command to obtain a list of geographic localization for established connections, extracted from netstat. Need geoiplookup command ( part of geoip package under CentOS)

echo start > battery.txt; watch -n 60 'date >> battery.txt'
2009-10-18 07:00:26
User: m33600
Functions: echo watch
0

Fully recharge your computer battery and start this script.

It will create or clean the file named battery.txt, print a start on it and every minute it will append a time stamp to it.

Batteries last few hours, and each hour will have 60 lines of time stamping. Really good for assuring the system was tested in real life with no surprises.

The last time stamp inside the battery.txt file is of interest. It is the time the computer went off, as the battery was dead!

Turn on your computer after that, on AC power of course, and open battery.txt. Read the first and last time stamps and now you really know if you can trust your computer sensors.

If you want a simple line of text inside the battery.txt file, use this:

watch -n 60 'date > battery.txt'

The time of death will be printed inside

weather() { lynx -dump "http://mobile.weather.gov/port_zh.php?inputstring=$*" | sed 's/^ *//;/ror has occ/q;2h;/__/!{x;s/\n.*//;x;H;d};x;s/\n/ -- /;q';}
ord() { printf "%d\n" "'$1"; }
2009-10-17 22:02:52
User: zude
Functions: printf
1

printf treats first char after single ' as numeric equivalent

for file in *.iso; do mkdir `basename $file | awk -F. '{print $1}'`; sudo mount -t iso9660 -o loop $file `basename $file | awk -F. '{print $1}'`; done
time dd if=/dev/zero of=TEST bs=4k count=512000
mkisofs -o XYZ.iso XYZ/
2009-10-17 16:28:47
User: eastwind
Functions: mkisofs
7

create iso image from directory . Usefull for virtualised machine

To create CD ISO image of directories that contain long file name or non-8.3 format (particularly if you want to burn the CD image for use in Windows system), use the -J option switch that generates Joliet directory records in addition to regular iso9660 file names. For example, to create CD image of Vista SP1 directory: mkisofs -o VitaSP1.iso -J VistaSP1

echo -n a | od -d | sed -n "s/^.* //gp"
2009-10-17 15:46:00
User: stf42
Functions: echo od sed
1

the shortest command for character 'a' i know

x=1 ; while [ $x -le 10 ] ; do lynx -dump http://www.alexa.com/siteinfo/http://[YOUR WEBSITE] | grep Global | sed 's/ \|Global\|\,//g' >> /var/log/alexa-stats.txt ; sleep 5h ; done &
2009-10-17 13:48:05
User: felix001
Functions: grep sed sleep
0

This will record the Alexa Traffic Stats to a file and run every 5 hours.

-- www.fir3net.com --

printf "%d\n" "'A" "'B"
chr () { echo -en "\0$(printf %x $1)"}
ord () { seq 1 127 | while read i; do echo `chr $i` $i; done | grep "^$1 " | cut -c '3-' }
2009-10-16 21:54:01
User: infinull
Functions: cut echo grep read seq
0

uses the previous "chr" function and uses it to create the inverse function "ord" by brute force.

It's slow, It's inelegant, but it works.

I thought I needed ord/chr to do a cartesian cipher in shell script a whie ago, but eventualy I realized I could get fancy with tr and do the same thing...

chr() { printf \\$(printf %o $1); }
argv=("$@"); rest=${argv[@]:1}; less -JMN +"/$1" `grep -l $1 $rest`
2009-10-16 17:36:16
User: lassel
Functions: less
Tags: bash less log grep
1

Really useful way to combine less and grep while browsing log files.

I can't figure out how to make it into a true oneliner so paste it into a script file called lgrep:

Usage:

lgrep searchfor file1 [file2 file3]

Advanced example (grep for an Exception in logfiles that starts with qc):

lgrep Exception $(find . -name "qc*.log")

history -c && rm -f ~/.bash_history
2009-10-16 13:48:20
Functions: rm
2

Note the space before the command; that prevents your history eliminating command from being recorded. ' history -c && rm -f ~/.bash_history' Both steps are needed. 'history -c' clears what you see in the history command. 'rm -f ~/.bash_history' deletes the history file in your home directory.