Commands by robinsonaarond (13)

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Get ssh server fingerprints
Get your server's fingerprints to give to users to verify when they ssh in. Publickey locations may vary by distro. Fingerprints should be provided out-of-band.

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"

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

python2 -m CGIHTTPServer
In case you need to test some CGI scripts this does the job. It also has the functionality of a http server. Enjoy!

List your installed Chromium extensions (with url to each page)
Gives you a list for all installed chrome (chromium) extensions with URL to the page of the extension. With this you can easy add a new Bookmark folder called "extensions" add every URL to that folder, so it will be synced and you can access the names from every computer you are logged in. ------------------------------------------------------------------------------------------------------------------ Only tested with chromium, for chrome you maybe have to change the find $PATH.

VI config to save files with +x when a shebang is found on line 1
Add this to .vimrc to automatically give scripts with a shebang (e.g., #!/usr/bin/perl) executable permissions when saving. Found @ http://stackoverflow.com/questions/817060/creating-executable-files-in-linux/817522#817522

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" }

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.

Check how far along (in %) your program is in a file
Imagine you've started a long-running process that involves piping data, but you forgot to add the progress-bar option to a command. e.g. $ xz -dc bigdata.xz | complicated-processing-program > summary . This command uses lsof to see how much data xz has read from the file. $ lsof -o0 -o -Fo FILENAME Display offsets (-o), in decimal (-o0), in parseable form (-Fo) This will output something like: . p12607 f3 o0t45187072 . Process id (p), File Descriptor (f), Offset (o) . We stat the file to get its size $ stat -c %s FILENAME . Then we plug the values into awk. Split the line at the letter t: -Ft Define a variable for the file's size: -s=$(stat...) Only work on the offset line: /^o/ . Note this command was tested using the Linux version of lsof. Because it uses lsof's batch option (-F) it may be portable. . Thanks to @unhammer for the brilliant idea.

List all duplicate directories
Very quick! Based only on the content sizes and the character counts of filenames. If both numbers are equal then two (or more) directories seem to be most likely identical. if in doubt apply: $ diff -rq path_to_dir1 path_to_dir2 AWK function taken from here: http://stackoverflow.com/questions/2912224/find-duplicates-lines-based-on-some-delimited-fileds-on-line


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