Commands by lavidaportland (3)

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create screencast (record text and audio simultaneously) using 'script' and 'arecord'
This shell function takes a single argument, which is used as the base name of the .wav, .timing and .session files created. To create a screencast: $ screencast test type and talk ... then type 'exit' or to exit the screencast. test.wav will contain the audio from your screencast. test.session will contain text and control characters needed to paint the screen test.timing will contain timing information needed to synch individual keystrokes in test.session with the audio. to play back: $ aplay test.wav & scriptreplay test.{timing,session} NOTE: because the shell function uses the variable "$!", and bash likes to expand '!' during history expansion, you will need to turn off bash's history before you enter the shell function. This can be achieved using the command $set +H

Rename all .jpeg and .JPG files to have .jpg extension
the "i" controls case sensitiveness. It's slightly inefficient since it uselessly renames .jpg to .jpg, but that's more than compensated by launching only one process instead of two, besides being shorter to write.

show rpm packages scriptlets

Show complete URL in netstat output
The -W switch of netstat makes it print complete URL of the connections, which otherwise by default is truncated to fit its default column size. Now to compensate for irregular column sizes, pipe the output to column (-t switch of column prints in tabular form). The only downside to this part is that the very first row, the header, goes pear shape.

diff will usually only take one file from STDIN. This is a method to take the result of two streams and compare with diff. The example I use to compare two iTunes libraries but it is generally applicable.
diff is designed to compare two files. You can also compare directories. In this form, bash uses 'process substitution' in place of a file as an input to diff. Each input to diff can be filtered as you choose. I use find and egrep to select the files to compare.

Show File System Hierarchy
Curious about differences between /bin, /usr/bin, and /usr/local/bin? What should be in the /sbin dir? Try this command to find out. Tested against Red Hat & OS X

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

Block the 6700 worst spamhosts
The above url contains over 6700 of the common ad websites. The command just pastes these into your /etc/hosts.

Download all .key files from your android device to your pc.

list block devices
Shows all block devices in a tree with descruptions of what they are.


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