Commands by bazzargh (4)

  • Show permissions of current directory and all directories upwards to /

    NB not 'namei -m .', as it slices the path you give it. Show Sample Output


    16
    namei -m $(pwd)
    bazzargh · 2012-07-24 15:27:20 6
  • Delimiter Hunting

    Search in decimal rather than hex. od dumps the character list, cut to remove offsets, sort -u gives the used characters. seq gives the comparison list, but we need this sorted alphabetically for comm, which does the filtering. I drop to perl to convert back to characters (is there a better way?) and then use od to dump them in a print-safe format. Show Sample Output


    0
    comm -13 <(od -vw1 -tu1 dummy.txt|cut -c9-|sort -u) <(seq 0 127|sort)|perl -pe '$_=chr($_)'|od -c
    bazzargh · 2012-01-09 01:32:20 8
  • find the biggest files recursively, no matter how many

    A different approach to the problem - maintain a small sorted list, print the largest as we go, then the top 10 at the end. I often find that the find and sort take a long time, and the large file might appear near the start of the find. By printing as we go, I get better feedback. The sort used in this will be much slower on perls older than 5.8. Show Sample Output


    -2
    find . -type f|perl -lne '@x=sort {$b->[0]<=>$a->[0]}[(stat($_))[7],$_],@x;splice(@x,11);print "@{$x[0]}";END{for(@x){print "@$_"}'
    bazzargh · 2012-01-08 14:43:43 4
  • one-line log format for svn

    the output of svn log is annoying to grep, since it spreads the useful info over multiple lines. This compacts the output down to one line so eg you can grep for a comment and see the rev, date & committer straight away. Updated: MUCH shorter, easier to remember. Now it just replaces newlines with spaces, except on '---' lines. Show Sample Output


    1
    svn log | perl -l40pe 's/^-+/\n/'
    bazzargh · 2011-10-14 16:02:22 7

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git pull all repos

Shows users and 'virtual users' on your a unix-type system
Shows a list of users that currently running processes are executing as. YMMV regarding ps and it's many variants. For example, you might need: $ ps -axgu | cut -f1 -d' ' | sort -u

send incoming audio to a Icecast server (giss.tv)
easy way to setup an "internet radio sation", pre-requisite, create an account at an icecast server, in this example, just created beforehand an account at giss.tv. Change the word password, with the respective real password you created at server. Make sure to have installed rec, oggnec, oggfwd and tee. I have a mixer connected at line in, so I can mix music and microphone. This also will produce a local recorded copy of the session, it will be called "streamdump.ogg"

Get all mac address
I prefer the ip command to ifconfig as ifconfig is supposedly going to be deprecated. Certain IP address aliases can only be seen with the ip command (such as the ones applied by RHCS).

find text in a file
this will find text in the directory you specify and give you line where it appears.

Convert JSON to YAML

randomize hostname and mac address, force dhcp renew. (for anonymous networking)
this string of commands will release your dhcp address, change your mac address, generate a new random hostname and then get a new dhcp lease.

Detect illegal access to kernel space, potentially useful for Meltdown detection
Based on capsule8 agent examples, not rigorously tested

Adjust gamma so monitor doesn't mess up your body's clock
[UPDATE: Now works for multiple connected outputs] I woke up around midnight with an urge to do some late night hacking, but I didn't want a bright monitor screwing up my body's circadian rhythm. I've heard that at night blue (short wavelength) lights are particularly bad for your diurnal clock. That may be a bunch of hooey, but it is true that redder (longer wavelength) colors are easier on my eyes at night. This command makes the screen dimmer and adjusts the gamma curves to improve contrast, particularly darkening blues and greens (Rɣ=2, Gɣ=3, Bɣ=4). To reset your screen to normal, you can run this command: $ xrandr | sed -n 's/ connected.*//p' | xargs -n1 -tri xrandr --output {} --brightness 1 --gamma 1:1:1 or, more briefly, $ xgamma -g 1 Note: The sed part is fragile and wrong. I'm doing it this way because of a misfeature in xrandr(1), which requires an output be specified but has no programmatic way of querying available outputs. Someone needs to patch up xrandr to be shell script friendly or at least add virtual outputs named "PRIMARY" and "ALL". . Todo: Screen should dim (gradually) at sunset and brighten at sunrise. I think this could be done with a self-resubmitting at job, but I'm running into the commandlinefu 127 character limit just getting the sunrise time: $ wget http://aa.usno.navy.mil/cgi-bin/aa_pap.pl --post-data=$(date "+xxy=%Y&xxm=%m&xxd=%d")"&st=WA&place=Seattle" -q -O- | sed -rn 's/\W*Sunrise\W*(.*)/\1/p' I hope some clever hacker comes up with a command line interface to Google's "OneBox", since the correct time shows up as the first hit when googling for "sunrise:cityname". . [Thank you to @flatcap for the sed improvement, which is much better than the head|tail|cut silliness I had before. And thank you to @braunmagrin for pointing out that the "connected" output may not be on the second line.]

Deleting / Ignoring lines from the top of a file
Output lines starting at line 2.

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