Commands using sleep (289)

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Which processes are listening on a specific port (e.g. port 80)
swap out "80" for your port of interest. Can use port number or named ports e.g. "http"

Search for classes in Java JAR files.

Hiding password while reading it from keyboard
Allow to read password in a script without showing the password inserted by the user

Create a persistent connection to a machine
Create a persistent SSH connection to the host in the background. Combine this with settings in your ~/.ssh/config: Host host ControlPath ~/.ssh/master-%r@%h:%p ControlMaster no All the SSH connections to the machine will then go through the persisten SSH socket. This is very useful if you are using SSH to synchronize files (using rsync/sftp/cvs/svn) on a regular basis because it won't create a new socket each time to open an ssh connection.

Set laptop display brightness
Run as root. Path may vary depending on laptop model and video card (this was tested on an Acer laptop with ATI HD3200 video). $ cat /proc/acpi/video/VGA/LCD/brightness to discover the possible values for your display.

Convert seconds to [DD:][HH:]MM:SS
Converts any number of seconds into days, hours, minutes and seconds. sec2dhms() { declare -i SS="$1" D=$(( SS / 86400 )) H=$(( SS % 86400 / 3600 )) M=$(( SS % 3600 / 60 )) S=$(( SS % 60 )) [ "$D" -gt 0 ] && echo -n "${D}:" [ "$H" -gt 0 ] && printf "%02g:" "$H" printf "%02g:%02g\n" "$M" "$S" }

Short Information about loaded kernel modules
Liked command 4077 so I improved it, by doing all text manipulation with sed. "Run this as root, it will be helpful to quickly get information about the loaded kernel modules." THX mohan43u

Ping all hosts on 192.168.1.0/24
Pings all the hosts on 192.168.1.0/24 in parallel, so it is very fast. Alive host IP addresses are echoed to stdout as pings are responded to.

Watch the disk fill up
While copying a large file that may take up a good chunk of your hard drive, start the copy and run this command concurrently. It will print out the disk information every second. It's pretty handy when you have a large copy with nothing to monitor the progress.

connect via ssh using mac address
Instead of looking for the right ip address, just pick whatever address you like and set a static ip mapping.


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