Commands by BigZ (4)

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backup and remove files with access time older than 5 days.
create an archive of files with access time older than 5 days, and remove original files.

mean color of an image
You can get the mean value for the colours in an image. Then you can determine, in general, how dark or bright is the image and run some other actions based on that. I'll recommend to readjust the brightness of the images using +sigmoidal-contrast option of imagemagick convert command.

Create QR codes from a URL.
like 7300, but doesn't clutter your working directory with old qr.*.png files. This will get the QR barcode, and send it right into ImageMagick's 'display' tool. Usage is the same as 7300; just call this function followed by the URL: $ qrurl http://xkcd.com

burn a isofile to cd or dvd
cdrecord must be installed. usefull alias: $alias burniso='cdrecord -v dev=/dev/cdrom' now iso burning is like. $burniso image.iso

Monitoring wifi connection by watch command (refresh every 3s), displaying iw dump info and iwconfig on wireless interface "wlan0"

Find all the links to a file
This command finds and prints all the symbolic and hard links to a file. Note that the file argument itself be a link and it will find the original file as well. You can also do this with the inode number for a file or directory by first using stat or ls or some other tool to get the number like so: $ stat -Lc %i file or $ ls -Hid file And then using: $ find -L / -inum INODE_NUMBER -exec ls -ld {} +

See the 10 programs the most used

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.

run complex remote shell cmds over ssh, without escaping quotes
Much simpler method. More portable version: ssh host -l user "`cat cmd.txt`"

check open ports (both ipv4 and ipv6)
While `lsof` will work, why not use the tool designed explicitly for this job? (If not run as root, you will only see the names of PID you own)


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