Commands by bugmenot

Commands by bugmenot (65)

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Create a tar archive with all files of a certain type found in present dir and subdirs

Note: the tar archive must not exist in order to create it. If exists it will only be updated and no already existent files in present search will still remain in the tar archive. The update option has to be used instead of create because the command tar may be executed more than once depending on the number of arguments that find throws. You can see maximum number of arguments with 'getconf ARG_MAX'
This is sample output - yours may be different.
4

find ./ -type f -name "*.txt" -exec tar uvf myarchives.tar {} +

bugmenot · 2012-07-29 00:35:58 2
Emulating netcat -e (netcat-traditional or netcat-openbsd) with the gnu-netcat

Then just nc servername 2600 and ./script.sh kill the client with ctrl+c. You can reconnect several times. kill the server with exit
This is sample output - yours may be different.
8

mkfifo foo ; nc -lk 2600 0<foo | /bin/bash 1>foo

bugmenot · 2012-07-29 00:33:41 0
Remove from PATH paths containing a string

If there are spaces won't work.
This is sample output - yours may be different.
0

export PATH= $(echo $PATH | tr ':' '\n' | awk '!/matching string/' | paste -sd:)

bugmenot · 2012-07-29 00:30:54 0
grep lines containing two consecutive hyphens
This is sample output - yours may be different.
0

grep "\-\-" file

bugmenot · 2012-07-29 00:26:14 0
Replace duplicate files by hardlinks
This is sample output - yours may be different.
1

fdupes -r -1 Neu | while read line; do j="0"; buf=""; for file in ${line[*]}; do if [ "$j" == "0" ]; then j="1"; buf=$file; else ln -f $buf $file; fi; done; done

bugmenot · 2012-01-20 22:26:54 0
Kick user
This is sample output - yours may be different.
2

killall -u username

bugmenot · 2011-11-24 20:26:38 0
Create strong, but easy to remember password

Why remember? Generate! Up to 48 chars, works on any unix-like system (NB: BSD use md5 instead of md5sum) Show Sample Output
This is sample output - yours may be different.
```
YzFj3mM1YzAjNJQ2
```
24

read -s pass; echo $pass | md5sum | base64 | cut -c -16

bugmenot · 2011-11-24 20:23:47 9
capture selected window

I think, this is a shorter one :)
This is sample output - yours may be different.
1

scrot -s /tmp/file.png

bugmenot · 2011-11-24 20:00:13 0

Display command options without typing --help

Type out the command and simply press to see the list of options for that command without having to type --help. Show Sample Output

-7

<Ctrl+o>

bugmenot · 2011-08-19 00:09:53 9

Generate an XKCD #936 style 4 word password

The first grep rejects capitalised words since the dict has proper nouns in it that you mightn't want to use. The second grep rejects words with ending in apostrophe s, and the third forces the words to be at least 15 characters long. Show Sample Output
This is sample output - yours may be different.
```
counterproductive unreasonableness multimillionaires extemporaneously
```
-2

cat /usr/share/dict/words | grep -P ^[a-z].* | grep -v "'s$" | grep -Pv ^.\{1,15\}$ | shuf -n4 | tr '\n' ' ' | sed 's/$/\n/'

bugmenot · 2011-08-15 01:03:48 3
Countdown Clock
This is sample output - yours may be different.
0

MIN=10 && for i in $(seq $(($MIN*60)) -1 1); do printf "\r%02d:%02d:%02d" $((i/3600)) $(( (i/60)%60)) $((i%60)); sleep 1; done

bugmenot · 2011-02-20 10:24:22 0
Backup to tape, rewind and check md5

Backups $DIR_TO_BACKUP into tape, creating on the fly a MD5SUM file of the backup. Then rewinds one record on tape and checks if it's well written.
This is sample output - yours may be different.
0

tar -cvf - $DIR_TO_BACKUP | tee >(md5sum > backup_md5.txt) > /dev/st0 && mt -f /dev/nst0 bsfm 1 && md5sum -c backup_md5.txt < /dev/st0

bugmenot · 2011-01-27 20:57:36 1
snapshot partition for consistent backups with minimal downtime

(FreeBSD) Once you've made the snapshot you can resume any stopped services and then back up the file system (using the snapshot) without having to worry about changed files. When finished, the snapshot can be removed : umount /mnt mdconfig -d -u 1 rm /var/.snap/snap_var_`date "+%Y-%m-%d"`
This is sample output - yours may be different.
0

mksnap_ffs /var /var/.snap/snap_var_`date "+%Y-%m-%d"` ; mdconfig -a -t vnode -f /var/.snap/snap_var_`date "+%Y-%m-%d"` -u 1; mount -r /dev/md1 /mnt

bugmenot · 2010-09-18 11:37:03 0
find available cpu frequencies on FreeBSD

Once you know the available frequencies for your CPU, they can be used to do things like set minimum CPU frequency for powerd so that it doesn't ramp down too slow on a server : /etc/sysctl.conf or /boot/loader.conf: debug.cpufreq.lowest=DESIRED FREQ HERE or at terminal sysctl debug.cpufreq.lowest=DESIRED FREQ HERE Show Sample Output
This is sample output - yours may be different.
```
dev.cpu.0.freq_levels: 1200/13000 1050/11375 900/9750 750/8125 600/6500
```
2

sysctl dev.cpu.0.freq_levels

bugmenot · 2010-09-18 11:19:46 0
Purge configuration files of removed packages on debian based systems

also search with aptitude search '~c'
This is sample output - yours may be different.
18

aptitude purge '~c'

bugmenot · 2010-09-13 12:15:00 1
< 1 2 3

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Find the process you are looking for minus the grepped one

faster ;) but your idea is really cool

Which processes are listening on a specific port (e.g. port 80)

swap out "80" for your port of interest. Can use port number or named ports e.g. "http"

Show Directories in the PATH Which does NOT Exist

I often need to know of my directory in the PATH, which one DOES NOT exist. This command answers that question * This command uses only bash's built-in commands * The parentheses spawn a new sub shell to prevent the modification of the IFS (input field separator) variable in the current shell

Sort a character string

Sorts a character string, using common shell commands.

vi a remote file with port

If you are running sshd on different port use above this command to edit/view remote file with vi/vim. In above example I am using port 12345.

change exif data in all jpeg's

this takes every jpg in the current directory and changes the exif data for manufactur and model. in my case i change it to LOMO LC-A because my scanner puts his data in there :]

Find usb device in realtime

Using this command you can track a moment when usb device was attached.

Convert seconds to [DD:][HH:]MM:SS

Converts any number of seconds into days, hours, minutes and seconds. sec2dhms() { declare -i SS="$1" D=$(( SS / 86400 )) H=$(( SS % 86400 / 3600 )) M=$(( SS % 3600 / 60 )) S=$(( SS % 60 )) [ "$D" -gt 0 ] && echo -n "${D}:" [ "$H" -gt 0 ] && printf "%02g:" "$H" printf "%02g:%02g\n" "$M" "$S" }

back ssh from firewalled hosts

host B (you) redirects a modem port (62220) to his local ssh. host A is a remote machine (the ones that issues the ssh cmd). once connected port 5497 is in listening mode on host B. host B just do a ssh 127.0.0.1 -p 5497 -l user and reaches the remote host'ssh. This can be used also for vnc and so on.

recursive search and replace old with new string, inside files

Search and replace recursively. :-) Shorter and simpler than the others. And allows more terms: replace old new [old new ...] -- `find -type f`

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