Commands by denni (2)

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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"

print first n characters of any file in human readble form using hexdump
Usefull to determine unknown file type

ssh batch jobs: query hundreds of hosts with an ssh command
Need to query hundreds of hosts with an ssh command ? Of course you'll have setup keys on all your remote HOSTs. But in the case a key is not present this command will skip that node, proceeding on to the next. -t: Force pseudo-tty allocation. This can be used to execute arbitrary screen-based programs on a remote machine. Also prevents unwanted stty messages being sent to console -q: Quiet mode. -o "BatchMode yes" If set to yes, passphrase/password querying will be disabled. This option is useful in scripts and other batch jobs where no user is present

Calculate days on which Friday the 13th occurs (inspired from the work of the user justsomeguy)
Friday is the 5th day of the week, monday is the 1st. Output may be affected by locale.

Take screenshot through SSH
Of course it requires import command, from imagemagick tools, but it's simpler to type, and imagemagick is usefull anyway.

Get playlist for Livestream on YouTube

Number of CPU's in a system
This appears to do the same. Utility is verified to be present on Ubuntu and OpenSuse out-of-the-box.

most changed files in domains by rdiff-backup output

start a vnc server session to connect to a gdm login screen

Search for packages, ranked by popularity
This will take the packages matching a given `apt-cache search` query (a collection of AND'd words or regexps) and tell you how popular they are. This is particularly nice for those times you have to figure out which solution to use for e.g. a PDF reader or a VNC client. Substitute "ubuntu.com" for "debian.org" if you want this to use Ubuntu's data instead. Everything else will work perfectly.


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