Commands by nanopino (1)

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Print every Nth line (to a maximum)
Thanks to knoppix5 for the idea :-) Print selected lines from a file or the output of a command. Usage: $ every NTH MAX [FILE] Print every NTH line (from the first MAX lines) of FILE. If FILE is omitted, stdin is used. The command simply passes the input to a sed script: $ sed -n -e "${2}q" -e "0~${1}p" ${3:-/dev/stdin} print no output $ sed -n quit after this many lines (controlled by the second parameter) $ -e "${2}q" print every NTH line (controlled by the first parameter) $ -e "0~${1}p" take input from $3 (if it exists) otherwise use /dev/stdin ${3:-/dev/stdin}

Check if a web page has changed last time checked.
Checks if a web page has changed. Put it into cron to check periodically. Change http://www.page.de/test.html and [email protected] for your needs.

Watch the National Debt clock
The idea was originally stolen from Linux Journal. 'wget' pulls the debt clock and 'sed' reformats it for general consumption. Prefacing the command with 'watch' simply sets an interval - in this case every 10 seconds.

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

Find if the command has an alias

sqlite3 cmd to extract Firefox bookmarks from places.sqlite
Found this useful query at http://id.motd.org/pivot/entry.php?id=22. The b.parent=2 in the command refers to the bookmarks folder to extract. See the source webpage for additional info.

validate xml in a shell script using xmllint

the same as [Esc] in vim
Faster and more convinent than [Esc]

clean up syntax and de-obfuscate perl script
the command show can be run in vim, here is the same thing on the command line $ cat script.pl | perl -MO=Deparse | perltidy

Command line calculator
This opens a python command line. You can use math and random and float-division is enabled (without appending .0 to integers). I just don't know how to specify a standard precision.


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