Commands by linuxswords (5)

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Convert CSV to JSON
Replace 'csv_file.csv' with your filename.

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.

True random passwords using your microphone noise as seed
Generate a truly random password using noise from your microphone to seed the RNG. This will spit out 12 password with 12 characters each, but you can save this into a bash script and replace 'pwgen -ys 12 12' with 'pwgen $@' so you can pass any paramters to pwgen as you would normally do.

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"

Printing multiple years with Unix cal command
print multiple increasing years using cal - calendar -. You can also try $seq Start Increment End

Get your outgoing IP address

Kill a broken ssh connection
This is useful for example if you are on ssh in a server and the server goes down without letting you out. This is part of a larget sets of escape sequences provided by ssh. You can find them with ~? Here's the list: ~. - terminate connection (and any multiplexed sessions) ~B - send a BREAK to the remote system ~C - open a command line ~R - request rekey ~V/v - decrease/increase verbosity (LogLevel) ~^Z - suspend ssh ~# - list forwarded connections ~& - background ssh (when waiting for connections to terminate) ~? - this message ~~ - send the escape character by typing it twice (Note that escapes are only recognized immediately after newline.)

send a circular
don't need echo :P

pinky - user info
Gives information about user's home directory and real name and shell user is having.

File rotation without rename command
Rotates log files with "gz"-extension in a directory for 7 days and enumerates the number in file name. i.e.: logfile.1.gz > logfile.2.gz I needed this line due to the limitations on AIX Unix systems which do not ship with the rename command.


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