Commands by Vilemirth

Commands by Vilemirth (8)

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Check if variable is a number
This is sample output - yours may be different.
1

if [[ "$1" =~ ^[0-9]+$ ]]; then echo "Is a number"; fi

Vilemirth · 2013-02-15 19:05:34 12
convert single digit to double digits

Uses 'rename' to pad zeros in front of first existing number in each filename. The "--" is not required, but it will prevent errors on filenames which start with "-". You can change the "2d" to any number you want, equaling the total numeric output: aka, 4d = ????, 8d = ????????, etc. I setup a handful of handy functions to this effect (because I couldn't figure out how to insert a var for the value) in the form of 'padnum?', such as: padnum5 () { /usr/bin/rename 's/\d+/sprintf("%05d",$&)/e' -- $@ } Which would change a file "foo-1.txt" to "foo-00001.txt"
This is sample output - yours may be different.
6

rename 's/\d+/sprintf("%02d",$&)/e' -- $@

Vilemirth · 2013-02-14 18:29:18 10
transfer files locally to be sure that file permissions are kept correctly showing progress
This is sample output - yours may be different.
-1

cp -av source dest

Vilemirth · 2011-02-19 18:43:49 4
Find Duplicate Files (based on size first, then MD5 hash)

If you have the fdupes command, you'll save a lot of typing. It can do recursive searches (-r,-R) and it allows you to interactively select which of the duplicate files found you wish to keep or delete.
This is sample output - yours may be different.
24

fdupes -r .

Vilemirth · 2011-02-19 17:02:30 10
Copy a directory recursively without data/files
This is sample output - yours may be different.
2

find . -type d -exec mkdir /copy_location/{} \;

Vilemirth · 2011-02-18 23:50:07 5
Remove all the files except abc in the directory

Bash method to remove all files but "abc". It would be 'rm *~abc' in Zsh.
This is sample output - yours may be different.
0

rm *[!abc]

Vilemirth · 2011-01-25 19:41:41 5
Convert ascii string to hex
This is sample output - yours may be different.
1

echo "text" | hd

Vilemirth · 2010-07-20 15:40:52 6
Emptying a text file in one shot

% = buffer d = delete
This is sample output - yours may be different.
11

:%d

Vilemirth · 2010-07-15 20:03:21 6

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print all network interfaces' names and IPv4 addresses

ifconfig can't properly display interface's name longer 9 symbols,also it can't show IPs added thru ip command, so 'ip' should be used instead. This alias properly shows long names, bond interfaces and all interface aliases. loopback interface is ignored, since its IP is obvious

Get your external IP address ( 10 characters long )

Shortest url to a external IP-service, 10 characters.

Find usb device in realtime

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

Disable system bell in an X session

Execute this command in a terminal to disable the system-bell during X-session lifetime.

File rotation without rename command

Rotates log files with "gz"-extension in a directory for 7 days and enumerates the number in file name. i.e.: logfile.1.gz > logfile.2.gz I needed this line due to the limitations on AIX Unix systems which do not ship with the rename command.

List last opened tabs in firefox browser

Tuned for short command line - you can set the path to sessionstore.js more reliable instead of use asterixes etc. Usable when you are not at home and really need to get your actual opened tabs on your home computer (via SSH). I am using it from my work if I forgot to bookmark some new interesting webpage, which I have visited at home. Also other way to list tabs when your firefox has crashed (restoring of tabs doesn't work always). This script includes also tabs which has been closed short time before.

mtr, better than traceroute and ping combined

mtr combines the functionality of the traceroute and ping programs in a single network diagnostic tool. As mtr starts, it investigates the network connection between the host mtr runs on and HOSTNAME. by sending packets with purposly low TTLs. It continues to send packets with low TTL, noting the response time of the intervening routers. This allows mtr to print the response percentage and response times of the internet route to HOSTNAME. A sudden increase in packetloss or response time is often an indication of a bad (or simply over‐loaded) link.

Simultaneously running different Firefox profiles

After running $ firefox -ProfileManager and creating several different profiles, use this command to run multiple Firefox profiles simultaneously.

Check if you work on a virtual/physical machine in Linux

Command used to know if we are working on a virtual or physical machine. This command will use the dmidecode utility to retrieve hardware information of your computer via the BIOS. Run this command as root or with sudo.

Less a grep result, going directly to the first match in the first file

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")

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