Commands by camocrazed (9)

  • when using Gnome or KDE, you will have a hard time getting a screenshot of something like a login screen, or any other screen that occurs before the desktop environment is up and monitoring the printscreen key. (this probably applies for other DEs as well, but I haven't used them) What this command is meant to do is take a screenshot of an X window using a command you can run from your virtual terminals (actual text terminals, not just an emulator) To do this: Press CTRL+ALT+F1 to go to a virtual (text) terminal once your login window comes up Login to the virtual terminal and enter the command (you'll have to type it in) You should now have a file called screenshot.png in your home directory with your screenshot in it. For those of you who are new to the virtual terminal thing, you can use CTRL+ALT+F7 to get back to your regular GUI From http://www.gnome.org


    3
    chvt 7 ; sleep 2 ; DISPLAY=:0.0 import -window root screenshot.png
    camocrazed · 2010-08-20 17:28:49 1
  • Broaden your knowledge of the utilities available to you in no particular order whatsoever! Then use that knowledge to create more nifty one-liners that you can post here. =p Takes a random number modulo the number of files in $dir, prints the filename corresponding to that number, and passes it as an argument to man.


    -2
    dir="/bin"; man $(ls $dir |sed -n "$(echo $(( $RANDOM % $(ls $dir |wc -l | awk "{ print $1; }" ) + 1 )) )p")
    camocrazed · 2010-08-20 16:31:50 1
  • This will allow you to convert an audio file to wav format, and send it via ssh to a player on the other computer, which will open and play it there. Of course, substitute your information for the sound file and remote address You do not have to use paplay on the remote end, as it is a PulseAudio thing. If the remote end uses ALSA, you should use aplay instead. If it uses OSS, you should berate them about having a lousy sound system. Also, you're not limited to transmitting encoded as wav either, it's just that AFAIK, most systems don't come with mp3 codecs, but will play wav files fine. If you know SoX is installed on the remote end and has mp3 codecs, you can use the following instead: cat Klaxon.mp3 |ssh thelab@company.com play -t mp3 - this will transmit as mp3. Again, use your specific information. if you're not playing mp3s, use another type with the -t option


    7
    sox Klaxon.mp3 -t wav - |ssh thelab@company.com paplay
    camocrazed · 2010-07-29 23:23:39 0
  • This takes quite a while on my system. You may want to test it out with /bin first, or background it and keep working. If you want to get rid of the "No manual entry for [whatever]" and just have the [whatever], use the following sed command after this one finishes. sed -n 's/^No manual entry for \(.*\)/\1/p' nomanlist.txt Show Sample Output


    -2
    for file in $(ls /usr/bin ) ; do man -w $file 2>> nomanlist.txt >/dev/null ; done
    camocrazed · 2010-07-26 19:39:53 3
  • the tee command does fine with file names, but not so much with file descriptors, such as &2 (stderr). This uses process redirection to tee to the specified descriptor. In the sample output, it's being used to tee to stderr, which is connected with the terminal, and to wc -l, which is also outputting to the terminal. The result is the output of bash --version followed by the linecount Show Sample Output


    5
    tee >(cat - >&2)
    camocrazed · 2010-07-20 17:22:31 3
  • If you're going to use od, here's how to suppress the labels at the beginning. Also, it doesn't output the \x, hence the sed command at the end. Remove it for space separated hex values instead Show Sample Output


    4
    echo -n "text" | od -A n -t x1 |sed 's/ /\\x/g'
    camocrazed · 2010-07-14 15:31:36 1
  • first off, if you just want a random UUID, here's the actual command to use: uuidgen Your chances of finding a duplicate after running this nonstop for a year are about the same as being hit by a meteorite before finishing this sentence The reason for the command I have is that it's more provably unique than the one that uuidgen creates. uuidgen creates a random one by default, or an unencrypted one based on time and network address if you give it the -t option. Mine uses the mac address of the ethernet interface, the process id of the caller, and the system time down to nanosecond resolution, which is provably unique over all computers past, present, and future, subject to collisions in the cryptographic hash used, and the uniqueness of your mac address. Warning: feel free to experiment, but be warned that the stdin of the hash is binary data at that point, which may mess up your terminal if you don't pipe it into something. If it does mess up though, just type reset Show Sample Output


    0
    printf $(( echo "obase=16;$(echo $$$(date +%s%N))"|bc; ip link show|sed -n '/eth/ {N; p}'|grep -o -E '([[:xdigit:]]{1,2}:){5}[[:xdigit:]]{1,2}'|head -c 17 )|tr -d [:space:][:punct:] |sed 's/[[:xdigit:]]\{2\}/\\x&/g')|sha1sum|head -c 32; echo
    camocrazed · 2010-07-14 14:04:53 0
  • Change the number to change the number of spaces. Leaving it out defaults to 8. Leaving out the filename defaults to stdin. And to do it in reverse, you can use the unexpand command.


    -1
    expand -t 2 <filename>
    camocrazed · 2010-07-13 23:04:57 0
  • Same as another one I saw, just with a cleaner sed command Edit: updated the sed command to use the [[:xdigit:]] character class - more portable between locales Note that it will have a newline inserted after every 32 characters of input, due to the output of xxd Show Sample Output


    0
    echo -n 'text' | xxd -ps | sed 's/[[:xdigit:]]\{2\}/\\x&/g'
    camocrazed · 2010-07-13 21:46:30 0

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Make anything more awesome
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To connect to the shell run: $ nc server.example.org 2000

Convert GoogleCL gmail contacts to cone adress book
Full Command: $ google contacts list name,name,email|perl -pne 's%^((?!N\/A)(.+?)),((?!N\/A)(.+?)),([a-z0-9\._-]+\@([a-z0-9][a-z0-9-]*[a-z0-9]\.)+([a-z]+\.)?([a-z]+))%${1}:${3} %imx'|grep -oP '^((?!N\/A)(.+?)) ' | sort You'll need googlecl and python-gdata. First setup google cl via: $ google Then give your PC access $ google contacts list name,email Then do the command, save it or use this one to dump it in the cone-address.txt file in your home dir: $ google contacts list name,name,email | perl -p -n -e 's%^((?!N\/A)(.+?)),((?!N\/A)(.+?)),([a-z0-9\._-]+\@([a-z0-9][a-z0-9-]*[a-z0-9]\.)+([a-z]+\.)?([a-z]+))%${1}:${3} %imx' | grep -o -P '^((?!N\/A)(.+?)) ' | sort > ~/cone-adress.txt Then import into cone. It filters out multiple emails, and contacts with no email that have N/A. (Picasa photo persons without email for example...)

Download all videos in your Boxee queue
Gets all videos in your boxee queue with a URL associated with them and attempts to download each using get_flash_videos

Apply substitution only on the line following a marker
I've been auto-generating some complex GnuPlots; with multiplots the first plot of each group needs to be a 'plot' whereas the others need to be 'replots' to allow overplotting/autoscaling/etc to work properly. This is used to replace only the first instance of 'replot'.

Get HTTP status code with curl

Recursive grep of all c++ source under the current directory
I like this better than some of the alternatives using -exec, because if I want to change the string, it's right there at the end of the command line. That means less editing effort and more time to drink coffee.

Join lines and separate with spaces
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Recording the desktop and an application audio source for webcast
You will have to use the sound preferences (record) to choose the audio source and set it to internal.

get partitions that are over 50% usage


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