Commands by karel1980

Commands by karel1980 (4)

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Generat a Random MAC address

Just increase the 1 at the end if you want to generate more than one. (Alternative to "| head -n N" you could use the -b flag of od: -b $[6*N] Show Sample Output
This is sample output - yours may be different.
```
ca:41:5d:28:ad:a2
```
2

od /dev/urandom -w6 -tx1 -An|sed -e 's/ //' -e 's/ /:/g'|head -n 1

karel1980 · 2011-05-16 15:05:34 1
Delete all but the latest 5 files, ignoring directories
This is sample output - yours may be different.
1

ls -lt|grep ^-|awk 'NR>5 { print $8 }'|xargs -r rm

karel1980 · 2009-09-16 07:43:03 0
Merge ( directories [looking for improvement]

Using a GUI file managers you can merge directories (cut and paste). This command roughly does the same (it doesn't ask for confirmation (no problem for me) and it doesn't clean up the empty SRC directories (no problem, trivial). probably does the same: cp -l SRC TARGET; rm -rf SRC
This is sample output - yours may be different.
0

(cd SRC; find . -type d -exec mkdir TARGET/{} ";"; find . -type f -exec mv {} TARGET/{} ";")

karel1980 · 2009-08-17 12:35:48 4
Move all images in a directory into a directory hierarchy based on year, month and day based on exif information

This command would move the file "dir/image.jpg" with a "DateTimeOriginal" of "2005:10:12 16:05:56" to "2005/10/12/image.jpg". This is a literal example from the exiftool man page, very useful for classifying photo's. The possibilities are endless. Show Sample Output
This is sample output - yours may be different.
```
    1 directories scanned
    1 directories created
  222 image files updated
    1 image files unchanged
```
15

exiftool '-Directory<DateTimeOriginal' -d %Y/%m/%d dir

karel1980 · 2009-08-04 11:47:34 4

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system beep off

list files recursively by size

Fetch the Gateway Ip Address

This is to fetch the Gateway Ip Address of a machine. Use the below format to put the value in a variable if you wish to find the gateway ip in a script $GATEWAY=$(netstat -nr | awk 'BEGIN {while ($3!="0.0.0.0") getline; print $2}')

Create a mirror of a local folder, on a remote server

Create a exact mirror of the local folder "/root/files", on remote server 'remote_server' using SSH command (listening on port 22) (all files & folders on destination server/folder will be deleted)

Show the command line for a PID, converting nulls to spaces and a newline

If you cat the file, all the parts of the command line are bunched up. If you use tr to convert the nulls to spaces, you're still left without a newline unless you add another step. This command does everything for you.

print multiplication formulas

seq -s ' ' 1 9 | sed -n ':a;p;s/ *\w$//;h;/^$/t;b a;q' | tac | awk '{for(i=1;i

Display the output of a command from the first line until the first instance of a regular expression.

Slightly simpler version of previous sed command that does the same thing. In this case, the output will stop at the command, and the entire command will be terminated as well, instead of proceeding through the whole file.

Simple Video Surveillance by email

This takes a picture (with the web cam) every 5 minutes, and send the picture to your e-mail. Some systems support mail -a "References: " so that all video surveillance emails are grouped in a single email thread. To keep your inbox clean, it is still possible to filter and move to trash video surveillance emails (and restore these emails only if you really get robbed!) For instance with Gmail, emails sent to me+trash@gmail.com can be filtered with "Matches: DeliveredTo:me+trash@gmail.com"

one-line log format for svn

the output of svn log is annoying to grep, since it spreads the useful info over multiple lines. This compacts the output down to one line so eg you can grep for a comment and see the rev, date & committer straight away. Updated: MUCH shorter, easier to remember. Now it just replaces newlines with spaces, except on '---' lines.

Install pip with Proxy

Installs pip packages defining a proxy

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