Commands by duxklr (3)

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

Calculate days on which Friday the 13th occurs
Simply change the years listed in the first seq, and it will print out all the months in that span of years that have Friday the 13ths in them.

find and delete files smaller than specific size

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

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" }

Command to rename multiple file in one go
An entirely shell-based solution (should work on any bourne-style shell), more portable on relying on the rename command, the exact nature of which varies from distro to distro.

Mount SMB share with password containing special characters
If the password for the share your trying to mount contains special characters you can use URL escape characters. The above command uses an example as follows: username: user password: [email protected] URL Encoded password: p%40ss All credit goes to Richard York: http://www.smilingsouls.net/Blog/20110526100731.html Also check out this URL Decoder/Encoder to convert your passwords. http://meyerweb.com/eric/tools/dencoder/

Test sendmail
test if sendmail is installed and working.

Create a file of repeated, non-zero
dd can be used with /dev/zero to easily create a file of all zero-bytes. Pipe that through tr and use octal conversions to change the byte values from zero to 0xff (octal 0377). You can replace 0377 with the byte of your choice. You can also use \\0 and \\377 instead of the quoted version.

Write comments to your history.
A null operation with the name 'comment', allowing comments to be written to HISTFILE. Prepending '#' to a command will *not* write the command to the history file, although it will be available for the current session, thus '#' is not useful for keeping track of comments past the current session.


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