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Terminal - All commands - 11,929 results
du -sb *|sort -nr|head|awk '{print $2}'|xargs du -sh
~<press tab twice>
hexdump -e '90/1 "%_p" "\n"' /dev/mem | less
2009-05-12 16:20:57
User: copremesis
Functions: hexdump
4

see what's in your memory right now... sometimes you find passwords, account numbers and url's that were recently used. Anyone have a safe command to clear the memory without rebooting?

export HISTTIMEFORMAT="%F %T "
2009-05-12 14:36:42
User: fritz_monroe
Functions: export
32

History usually only gives the command number and the command. This will add a timestamp to the history file.

Note: this will only put the correct timestamp on commands used after the export is done. You may want to put this in your .bashrc

kudzu -p
2009-05-12 10:34:59
Functions: kudzu
-3

Kudzu is available on CentOS, used for configuring and detecting new hardware device installed, is also usefull for device listing.

tcs -f 8859-1 -t utf /some/file
2009-05-12 10:13:02
User: michauko
Tags: utf iso
8

I use it sometimes when I work on a french file transferred from a windows XP to a Debian-UTF8 system. Those are not correctly displayed: ? ? ? and so on

man tcs # for all charsets
egrep -v "^$|^[[:space:]]*#" /etc/some/file
2009-05-12 07:14:48
User: michauko
Functions: egrep
Tags: egrep
15

Shows a file without comments (at least those starting by #)

- removes empty lines

- removes lines starting by # or "some spaces/tabs then #'"

Useful when you want to quickly see what you have to customize on a freshly installed application without reading the comments that sometimes are a full 1000 lines documentation :)

While posting, I saw this http://www.commandlinefu.com/commands/view/1041/display-contents-of-a-file-wo-any-comments-or-blank-lines

But it's dirty and incomplete, to my mind

My original goal was to remove lines like "\t*#" but I can't figure out how to do a egrep '\t' on a command-line. Two workarounds if needed:

egrep -v 'press control + V then TAB then #' /your/file

or

egrep -v -f some_file /your/file #where some_file contains what you want to exclude, example a really inserted TAB
grep -i '<searchTerm>\|<someOtherSearchTerm>' <someFileName>
2009-05-11 23:05:54
User: scifisamurai
Functions: grep
-1

This is a simple but useful command to search for multiple terms in a file at once. This prevents you from having to do mutliple grep's of the same file.

fold -s -w 90 file.txt
2009-05-11 23:00:25
User: vincentp
Functions: fold
11

wraps text lines at the specified width (90 here).

-s option is to force to wrap on blank characters

-b count bytes instead of columns

echo 2006-10-10 | grep -c '^[0-9][0-9][0-9][0-9]-[0-9][0-9]-[0-9][0-9]$'
2009-05-11 22:18:43
User: rez0r
Functions: echo grep
-1

Quick and easy way of validating a date format of yyyy-mm-dd and returning a boolean, the regex can easily be upgraded to handle "in betweens" for mm dd or to validate other types of strings, ex. ip address.

Boolean output could easily be piped into a condition for a more complete one-liner.

growisofs -M /dev/dvd -J -r "directory name with files to add to DVD"
2009-05-11 12:44:32
User: vleolml
2

replace "directory name with files to add to DVD" with actual directory containing files you want to add to growable DVD

growisofs -Z /dev/dvd -J -r "directory name to burn on DVD"
2009-05-11 12:42:18
User: vleolml
1

replace "directory name to burn on DVD" with actual directory name that you want to copy on DVD

pkill
ifconfig eth0 hw ether 00:11:22:33:44:55
dd if=/dev/mem of=file.dump bs=1024 skip=0 count=1
unalias
function echox { echo `tput cup $(($(tput lines))) $(( ($(tput cols) - $(echo "${#1}"))/2 ))`"$1"`tput cup $(tput lines) $(( $(tput cols)-1 ))`; }
2009-05-10 23:24:49
Functions: echo tput
1
function echox { echo `tput cup $(($(tput lines))) $(( ($(tput cols) - $(echo "${#1}"))/2 ))`"$1"`tput cup $(tput lines) $(( $(tput cols)-1 ))`; }

echox prints given argument on bottom line center screen in terminal

function echoxy { echo `tput cup $(($(tput lines)/2)) $(( ($(tput cols) - $(echo "${#1}"))/2))`"$1"`tput cup $(tput lines) $(( $(tput cols)-1 ))`; }

exhoxy prints given argument center screen

function echos { echo `tput cup $(($(tput lines)-2)) $(($(tput cols)-$(echo ${#1})))&&tput sc`"$1"`tput cup $(($(tput lines)-2)) 0 && tput rc`; } while [ 1 ]; do echos "`date`"; done

echos prints date and time on second from last line (used as status message)

you can easily use these functions by placing them in your .bashrc file, make sure to source your .bashrc once you do

echo '{"json":"obj"}' | python -m simplejson.tool
2009-05-10 13:58:05
User: azeey
Functions: echo python
Tags: python json
11

You can use a site like http://www.jsonlint.com/ or use the command line to validate your long and complex json data. This is part of the simplejson package for python http://undefined.org/python/#simplejson.

Wrong json expression example:

echo '{ 1.2:3.4}' | python -m simplejson.tool

Expecting property name: line 1 column 2 (char 2)

find / \( -name "*.log" -o -name "*.mylogs" \) -exec ls -lrt {} \; | sort -k6,8 | head -n1 | cut -d" " -f8- | tr -d '\n' | xargs -0 rm
2009-05-10 10:45:48
User: ghazz
Functions: cut find head ls sort tr xargs
1

This works on my ubuntu/debian machines.

I suspect other distros need some tweaking of sort and cut.

I am sure someone could provide a shorter/faster version.

for i in `seq -w 1600` ; do links -dump http://www.robsjokes.com/$i/index.html | sed '/Random Joke/,/Next Joke/!d' | sed '/^$/,/^$/!d' >> ~/temp/Rob.jokes ; echo '%' >> ~/temp/Rob.jokes ; done
perl -lane 'print "$F[0]:$F[1]:$F[2]"' myfile
2009-05-09 21:30:55
Functions: perl
0

Consider this line :

random perl language this make possible is

is possible to rearrange words with $F perl variable and word index, starting from 0.

wmwave
2009-05-09 20:33:27
-4

wmwave is part of wmwave package, when launched display a small wireless link monitor on your desktop with noise, level and link power.

setfont cybercafe
2009-05-09 20:08:47
1

setfont load vga console font. The default font directory is usually in /lib/kbd/consolefonts. Setfont is part of kbd package. Tested on CentOS.

ethstatus -i eth0
2009-05-09 19:33:39
6

ethstatus part of ethstatus package, is a consolle based monitor for network interfaces. Nicely display on screen a real time summary about bandwidth, speed and packets.

echo $?
2009-05-09 17:32:23
Functions: echo
11

The variable ? contain the last exit status of a command, it can be printed for troubleshooting purpose.