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Commands by bugmenot

Commands by bugmenot from sorted by
Terminal - Commands by bugmenot - 43 results
cat /dev/urandom | pv -L 3m | dd bs=1M count=100 iflag=fullblock > /dev/null
2012-07-29 00:42:16
User: bugmenot
Functions: cat dd
6
Up
Down
Limit the transfer rate and size of data over a pipe

This example will close the pipe after transferring 100MB at a speed of 3MB per second.

Comments (2) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
find path -name '*' -type f -print0 | xargs -0 grep -n pattern1 | grep pattern2
2012-07-29 00:40:06
User: bugmenot
Functions: find grep xargs
1
Up
Down
Find inside files two different patterns in the same line and for matched files show number of matched lines

The option -print0 for find and -0 for grep help prevent issue with weird characters or spaces in filenames. Furthermore with xargs there is no limited number of arguments that find can throw.

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watch -n10 "if test -e run.txt ; then chmod +x script.sh && ./script.sh && rm run.txt || rm run.txt && echo > failed.txt ; fi"
2012-07-29 00:38:08
User: bugmenot
Functions: watch
0
Up
Down
How to run a shell script on a remote host using ftp

You can upload via ftp the script.sh in unix text format, and then upload a file called run.txt to execute once the script. Such script can be multiline. If the script fails a failed.txt will be generated that you can see via ftp.

Comments (1) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
find ./ -type f -name "*.txt" -exec tar uvf myarchives.tar {} +
2012-07-29 00:35:58
User: bugmenot
Functions: find tar
4
Up
Down
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'

Comments (2) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
mkfifo foo ; nc -lk 2600 0<foo | /bin/bash 1>foo
2012-07-29 00:33:41
User: bugmenot
Functions: mkfifo
7
Up
Down
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

Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
export PATH= $(echo $PATH | tr ':' '\n' | awk '!/matching string/' | paste -sd:)
2012-07-29 00:30:54
User: bugmenot
Functions: awk echo export paste tr
0
Up
Down
Remove from PATH paths containing a string

If there are spaces won't work.

Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
grep "\-\-" file
2012-07-29 00:26:14
User: bugmenot
Functions: grep
0
Up
Down
grep lines containing two consecutive hyphens
Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
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
2012-01-20 22:26:54
User: bugmenot
Functions: file ln read
1
Up
Down
Replace duplicate files by hardlinks
Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
killall -u username
2011-11-24 20:26:38
User: bugmenot
Functions: killall
Tags: killall user
2
Up
Down
Kick user
Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
read -s pass; echo $pass | md5sum | base64 | cut -c -16
2011-11-24 20:23:47
User: bugmenot
Functions: cut echo md5sum read
Tags: password md5 base64 passphrase
19
Up
Down
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 | Comments (9) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
scrot -s /tmp/file.png
2011-11-24 20:00:13
User: bugmenot
Tags: scrot
1
Up
Down
capture selected window

I think, this is a shorter one :)

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<Ctrl+o>
2011-08-19 00:09:53
User: bugmenot
Tags: bash hotkey
-7
Up
Down
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 | Comments (9) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
cat /usr/share/dict/words | grep -P ^[a-z].* | grep -v "'s$" | grep -Pv ^.\{1,15\}$ | shuf -n4 | tr '\n' ' ' | sed 's/$/\n/'
2011-08-15 01:03:48
User: bugmenot
Functions: cat grep sed tr
Tags: tr xkcd shuf
-2
Up
Down
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 | Comments (3) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
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
2011-02-20 10:24:22
User: bugmenot
Functions: printf seq sleep
Tags: timer counter
0
Up
Down
Countdown Clock
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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
2011-01-27 20:57:36
User: bugmenot
Functions: md5sum mt tar tee
0
Up
Down
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.

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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
2010-09-18 11:37:03
User: bugmenot
Functions: mount
Tags: backup snapshots
0
Up
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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"`

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sysctl dev.cpu.0.freq_levels
2010-09-18 11:19:46
User: bugmenot
Functions: sysctl
Tags: cpu powerd
2
Up
Down
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 | Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
aptitude purge '~c'
2010-09-13 12:15:00
User: bugmenot
Tags: Debian aptitude
12
Up
Down
Purge configuration files of removed packages on debian based systems

also search with aptitude search '~c'

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