Commands by greggster (7)

  • Edit 2 or more files in vim using vim -d

    Use vim's diff mode to edit two or more files in one window. The '+diffoff!' turns off diff highlighting when the session is started. Use ctrl+w + ctrl+w to switch between windows. Show Sample Output


    2
    vim -d '+diffoff!' file1 file2
    greggster · 2012-08-30 07:51:41 7
  • Sort specific lines while editing within vi

    Sort lines within vi editor. In this example sort lines 33-61 and lines 4-9 asciibetically. Show Sample Output


    6
    :33,61 !sort
    greggster · 2011-05-06 06:10:05 8
  • Deal with dot files safely

    rm -rf .* matches ".." and thus one goes up a level and wipes out more than intended. In bash, .??* safely accomplishes what one intends - remove those .files The ? matches most characters except "/", thus .?? does not match ../ and so one is safe. Show Sample Output


    0
    rm -rf .??*
    greggster · 2011-03-11 07:21:58 9
  • va - alias for editing aliases

    When setting up a new aliases file, or having creating a new file.. About every time after editing an aliases file, I source it. This alias makes editing alias a bit easier and they are useful right away. Note if the source failed, it will not echo "aliases sourced". Sub in vi for your favorite editor, or alter for ksh, sh, etc.


    7
    alias va='vi ~/.aliases; source ~/.aliases && echo "aliases sourced"'
    greggster · 2011-03-10 06:41:37 7
  • Find large files in current directory

    This is for bash - make an alias - also a good blueprint for making aliases that take arguments to functions. If for Solaris use "-size +${1}000000c" to replace "-size +${1}M" Show Sample Output


    0
    alias big='BIG () { find . -size +${1}M -ls; }; BIG $1'
    greggster · 2011-03-10 06:33:00 7
  • do something else while waiting for an event, such as reboot

    until (ssh root@10.1.1.39 2> /dev/null); do date; sleep 15; done In this case will execute "date" then "sleep 15" until we are able to ssh into server, such as after a reboot Could also be like: until ( ping 10.1.1.39 1> /dev/null); do echo "server 10.1.1.39 is down"; sleep 15; done Show Sample Output


    8
    until (ssh root@10.1.1.39 2> /dev/null); do date; sleep 15; done
    greggster · 2011-03-08 08:42:12 9
  • cd to (or operate on) a file across parallel directories

    This is useful for quickly jumping around branches in a file system, or operating on a parellel file. This is tested in bash. cd to (substitute in PWD, a for b) where PWD is the bash environmental variable for the "working directory" Show Sample Output


    7
    cd ${PWD/a/b}
    greggster · 2011-03-03 06:27:12 11

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Get AWS temporary credentials ready to export based on a MFA virtual appliance
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The Hidden PS
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