Commands by taliver (5)


  • 2
    leapyear() { [ $(date -d "Dec 31, $1" +%j) == 366 ] && echo leap || echo not leap; }
    taliver · 2010-03-30 20:13:56 36
  • Slightly simpler version of previous sed command that does the same thing. In this case, the output will stop at the command, and the entire command will be terminated as well, instead of proceeding through the whole file.


    1
    command | sed '/regex/q'
    taliver · 2009-12-29 14:52:41 3
  • Uses the dumb terminal option in gnuplot to plot a graph of frequencies. In this case, we are looking at a frequency analysis of words in all of the .c files. Show Sample Output


    5
    cat *.c | { printf "se te du\nplot '-' t '' w dots\n"; tr '[[:upper:]]' '[[:lower:]]' | tr -s [[:punct:][:space:]] '\n' | sort | uniq -c | sort -nr | head -n 100 | awk '{print $1}END{print "e"}'; } | gnuplot
    taliver · 2009-11-20 14:53:26 7
  • This is a quick hack to make a gcc caller. Since it runs with gcc instead of tcc, it's a bit more trustworthy as far as the final answers of things go. Show Sample Output


    -3
    alias cstdin='echo "Ctrl-D when done." && gcc -Wall -o ~/.stdin.exe ~/.stdin.c && ~/.stdin.exe'
    taliver · 2009-11-19 16:38:51 4
  • This uses urandom to produce a random password. The random values are uuencoded to ensure only printable characters. This only works for a number of characters between 1 and 60. Show Sample Output


    -3
    mkpasswd() { head -c $(($1)) /dev/urandom | uuencode - | sed -n 's/.//;2s/\(.\{'$1'\}\).*/\1/p' ;}
    taliver · 2009-11-19 14:27:52 5

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escape any command aliases
e.g. if rm is aliased for 'rm -i', you can escape the alias by prepending a backslash: rm [file] # WILL prompt for confirmation per the alias \rm [file] # will NOT prompt for confirmation per the default behavior of the command

watch iptables counters
This will allow you to watch as matches occur in real-time. To filter out only ACCEPT, DROP, LOG..etc, then run the following command: watch 'iptables -nvL | grep -v "0 0" && grep "ACCEPT"' The -v is used to do an inverted filter. ie. NOT "0 0"

Backup with versioning
Apart from an exact copy of your recent contents, also keep all earlier versions of files and folders that were modified or deleted. Inspired by EVACopy http://evacopy.sourceforge.net

validate json
I have this saved as jsonlint chmodded +x and file.js is instead $1, but YMMV

Change wallpaper for xfce4 >= 4.6.0
Simply changes the wallpaper of xfce4 from the command line. Not for multiple displays.

Rename files in batch

grep certain file types recursively
-exec works better and faster then using a pipe

Generate random valid mac addresses
Python Alternative

Lines per second in a log file
Another way of counting the line output of tail over 10s not requiring pv. Cut to have the average per second rate : tail -n0 -f access.log>/tmp/tmp.log & sleep 10; kill $! ; wc -l /tmp/tmp.log | cut -c-2 You can also enclose it in a loop and send stderr to /dev/null : while true; do tail -n0 -f access.log>/tmp/tmp.log & sleep 2; kill $! ; wc -l /tmp/tmp.log | cut -c-2; done 2>/dev/null

Speak the top 6 lines of your twitter timeline every 5 minutes.....
Pump up the chatter, run this script on a regular basis to listen to your twitter timeline. This is a rough first cut using several cli clips I have spotted around. There is no facility to not read those things already read to you. This could also easily be put in a loop for timed onslaught from the chatterverse, though I think it might violate several pointsof the Geneva Convention UPDATE - added a loop, only reads the first 6 twits, and does this every 5 mins.


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