Commands tagged unique (4)

  • Reads stdin, and outputs each line only once - without sorting ahead of time. This does use more memory than your system's sort utility.


    4
    perl -ne 'print if !$a{$_}++'
    doherty · 2011-02-17 02:18:44 8
  • Once you get into advanced/optimized scripts, functions, or cli usage, you will use the sort command alot. The options are difficult to master/memorize however, and when you use sort commands as much as I do (some examples below), it's useful to have the help available with a simple alias. I love this alias as I never seem to remember all the options for sort, and I use sort like crazy (much better than uniq for example). # Sorts by file permissions find . -maxdepth 1 -printf '%.5m %10M %p\n' | sort -k1 -r -g -bS 20% 00761 drwxrw---x ./tmp 00755 drwxr-xr-x . 00701 drwx-----x ./askapache-m 00644 -rw-r--r-- ./.htaccess # Shows uniq history fast history 1000 | sed 's/^[0-9 ]*//' | sort -fubdS 50% exec bash -lxv export TERM=putty-256color Taken from my http://www.askapache.com/linux-unix/bash_profile-functions-advanced-shell.html Show Sample Output


    3
    alias sorth='sort --help|sed -n "/^ *-[^-]/s/^ *\(-[^ ]* -[^ ]*\) *\(.*\)/\1:\2/p"|column -ts":"'
    AskApache · 2010-06-10 21:30:31 10
  • Uniq command is mostly used in combination with sort command, as uniq removes duplicates only from a sorted file. i.e In order for uniq to work, all the duplicate entries should be in the adjacent lines. Show Sample Output


    0
    sort namesd.txt | uniq
    ankush108 · 2012-06-26 19:22:34 7
  • The following displays only the entries that are duplicates. Show Sample Output


    0
    sort namesd.txt | uniq ?cd
    ankush108 · 2012-06-26 19:23:58 4

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Clear all Windows Event Log entries (cygwin)
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delete multiple files with spaces in filenames (with confirmation)
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Grab the first 3 octets of your ip addresses
For machines that have many ip blocks spanning different Class C's, this will show which ones.

Get IP from hostname

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Stop Flash from tracking everything you do.
Brute force way to block all LSO cookies on a Linux system with the non-free Flash browser plugin. Works just fine for my needs. Enjoy.


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