Commands by Mikachu (3)

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archive all files containing local changes (svn)
Create a tgz archive of all the files containing local changes relative to a subversion repository. Add the '-q' option to only include files under version control: $svn st -q | cut -c 8- | sed 's/^/\"/;s/$/\"/' | xargs tar -czvf ../backup.tgz Useful if you are not able to commit yet but want to create a quick backup of your work. Of course if you find yourself needing this it's probably a sign you should be using a branch, patches or distributed version control (git, mercurial, etc..)

check the status of 'dd' in progress (OS X)
"killall -USR1 dd" does not work in OS X for me. However, sending INFO instead of USR1 works.

exclude file(s) from rsync
rsyncs files to a server excluding listed files also a file can be used to exclude common exclude rules and/or to exclude a ton of files, like so: $rsync --exclude-from '~/.scripts/exclude.txt' where exclude.txt has one rule per line: *.mp3 *.svn*

Check if a process is running
Send signal 0 to the process. The return status ($?) can be used to determine if the process is running. 0 if it is, non-zero otherwise.

Kill any process with one command using program name
Somtime one wants to kill process not by name of executable, but by a parameter name. In such cases killall is not suitable method.

Inverted cowsay
It's quite fun to invert text using "flip.pl" (ref: http://ubuntuforums.org/showthread.php?t=2078323 ). Slightly more challenging is to flip a whole "cowsay". :-)

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

back ssh from firewalled hosts
host B (you) redirects a modem port (62220) to his local ssh. host A is a remote machine (the ones that issues the ssh cmd). once connected port 5497 is in listening mode on host B. host B just do a ssh 127.0.0.1 -p 5497 -l user and reaches the remote host'ssh. This can be used also for vnc and so on.

Create a tar of directory structure only
The original suggestion did not work for me, when operating on folders located on an external mount (ie other than the root device) in Ubuntu. A variation using xargs does the trick.

IFS - use entire lines in your for cycles
When you use a "for" construct, it cycles on every word. If you want to cycle on a line-by-line basis (and, well, you can't use xargs -n1 :D), you can set the IFS variable to .


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