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 1
  • 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 0
  • 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 1
  • 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 1
  • 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 2

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I noticed some spammer posted an advertisement here for "not bad" encryption. Unfortunately, their software only runs under Microsoft Windows and fails to work from the commandline. My shell script improves upon those two aspects, with no loss in security, using the exact same "military-grade" encryption technology, which has the ultra-cool codename "ROT-13". For extra security, I recommend running ROT-13 twice.

Colorful man
That command installs "most" and make this command as the default man reader. The "most" works like "less" (the current man reader), but it render colors for manpages and may do more things. Read "man most". You can see a preview here: http://www.dicas-l.com.br/dicas-l/20090718.php

Randomize lines in a file
Works in sort (GNU coreutils) 7.4, don't know when it was implemented but sometime the last 6 years.

Function to check whether a regular file ends with a newline
tail -c 1 "$1" returns the last byte in the file. Command substitution deletes any trailing newlines, so if the file ended in a newline $(tail -c 1 "$1") is now empty, and the -z test succeeds. However, $a will also be empty for an empty file, so we add -s "$1" to check that the file has a size greater than zero. Finally, -f "$1" checks that the file is a regular file -- not a directory or a socket, etc.

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

How much RAM is Apache using?
Display the amount of memory used by all the httpd processes. Great in case you are being Slashdoted!

rename all images in folder with prefix of date and time from exif data
imagemagick is required


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