Commands tagged upgrade (9)

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A "Web 2.0" domain name generator and look for register availability
You would need pwgen installed first, on ubuntu you can get it by apt-get $ sudo apt-get install pwgen

host - DNS lookup utility
host is a simple utility for performing DNS lookups. It is normally used to convert names to IP addresses and vice versa. When no arguments or options are given, host prints a short summary of its command line arguments and options.

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.

Print every Nth line
Sometimes commands give you too much feedback. Perhaps 1/100th might be enough. If so, every() is for you. $ my_verbose_command | every 100 will print every 100th line of output. Specifically, it will print lines 100, 200, 300, etc If you use a negative argument it will print the *first* of a block, $ my_verbose_command | every -100 It will print lines 1, 101, 201, 301, etc The function wraps up this useful sed snippet: $ ... | sed -n '0~100p' don't print anything by default $ sed -n starting at line 0, then every hundred lines ( ~100 ) print. $ '0~100p' There's also some bash magic to test if the number is negative: we want character 0, length 1, of variable N. $ ${N:0:1} If it *is* negative, strip off the first character ${N:1} is character 1 onwards (second actual character).

Pipe a textfile to vim and move the cursor to a certain line
This command is more for demonstrating piping to vim and jumping to a specific line than anything else. Exit vim with :q! +23 jumps to line 23 - make vim receive the data from the pipe

Get AWS temporary credentials ready to export based on a MFA virtual appliance
You might want to secure your AWS operations requiring to use a MFA token. But then to use API or tools, you need to pass credentials generated with a MFA token. This commands asks you for the MFA code and retrieves these credentials using AWS Cli. To print the exports, you can use: `awk '{ print "export AWS_ACCESS_KEY_ID=\"" $1 "\"\n" "export AWS_SECRET_ACCESS_KEY=\"" $2 "\"\n" "export AWS_SESSION_TOKEN=\"" $3 "\"" }'` You must adapt the command line to include: * $MFA_IDis ARN of the virtual MFA or serial number of the physical one * TTL for the credentials

mean color of an image
You can get the mean value for the colours in an image. Then you can determine, in general, how dark or bright is the image and run some other actions based on that. I'll recommend to readjust the brightness of the images using +sigmoidal-contrast option of imagemagick convert command.

change dinosaur poop into gold
if firefox is running the database is locked, so you need to copy the places.sqlite file temporarily somewhere to be able to query it...

Watch active calls on an Asterisk PBX
This handles when you have a single call or channel. Other commands will strip out the result if there is a single channel or call active because the output changes the noun to be singular instead of plural.

Edit all files found having a specific string found by grep
The grep switches eliminate the need for awk and sed. Modifying vim with -p will show all files in separate tabs, -o in separate vim windows. Just wish it didn't hose my terminal once I exit vim!!


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