Commands by bugmenot

Commands by bugmenot (66)

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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.
This is sample output - yours may be different.
0

watch -n10 "if test -e run.txt ; then chmod +x script.sh && ./script.sh && rm run.txt || rm run.txt && echo > failed.txt ; fi"

bugmenot · 2012-07-29 00:38:08 1
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
```
22

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
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Show drive names next to their full serial number (and disk info)

Convert JSON to YAML

Requires installing json2yaml via npm: npm install -g json2yaml (can also pipe from stdin) Ref: https://www.npmjs.com/package/json2yaml

Watch the progress of 'dd'

run this in another terminal, were xxxx is the process ID of the running dd process. the progress will report on the original terminal that you ran dd on

git pull all repos

How to trim a video using ffmpeg

Will trim the video to 4 seconds starting from the beginning. The -vcodec , -acodec options are required so that ffmpeg knows in what video/audio format you want for the new video.

list block devices

Shows all block devices in a tree with descruptions of what they are.

list files recursively by size

copy timestamps of files from one location to another - useful when file contents are already synced but timestamps are wrong.

Sometimes when copying files from one place to another, the timestamps get lost. Maybe you forgot to add a flag to preserve timestamps in your copy command. You're sure the files are exactly the same in both locations, but the timestamps of the files in the new home are wrong and you need them to match the source. Using this command, you will get a shell script (/tmp/retime.sh) than you can move to the new location and just execute - it will change the timestamps on all the files and directories to their previous values. Make sure you're in the right directory when you launch it, otherwise all the touch commands will create new zero-length files with those names. Since find's output includes "." it will also change the timestamp of the current directory. Ideally rsync would be the way to handle this - since it only sends changes by default, there would be relatively little network traffic resulting. But rsync has to read the entire file contents on both sides to be sure no bytes have changed, potentially causing a huge amount of local disk I/O on each side. This could be a problem if your files are large. My approach avoids all the comparison I/O. I've seen comments that rsync with the "--size-only" and "--times" options should do this also, but it didn't seem to do what I wanted in my test. With my approach you can review/edit the output commands before running them, so you can tell exactly what will happen. The "tee" command both displays the output on the screen for your review, AND saves it to the file /tmp/retime.sh. Credit: got this idea from Stone's answer at http://serverfault.com/questions/344731/rsync-copying-over-timestamps-only?rq=1, and combined it into one line.

Readd all files is missing from svn repo

When working on a big proeject with SVN, you create quite much files, for now! Can just sit here and type svn add for all of them! svn status will return a list of all of file which get ?(not add), "M"(Modified), "D"(Deleted)! This code just grep "?" flag, then add it into SVN again!

How to run a command on a list of remote servers read from a file

The important thing to note in this command, is the "-n" flag.

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