Commands by casechen (1)

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Backup with versioning
Apart from an exact copy of your recent contents, also keep all earlier versions of files and folders that were modified or deleted. Inspired by the excellent EVACopy http://evacopy.sourceforge.net

recursively remove BOM

Suppress output of loud commands you don't want to hear from

Extract tarball from internet without local saving

Quickly (soft-)reboot skipping hardware checks
If you are doing some tests which require reboots (e. g. startup skripts, kernel module parameters, ...), this is very time intensive, if you have got a hardware with a long pre-boot phase due to hardware checks. At this time, kexec can help, which only restarts the kernel with all related stuff. First the kernel to be started is loaded, then kexec -e jumps up to start it. Is as hard as a reboot -f, but several times faster (e. g. 1 Minute instead of 12 on some servers here).

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

get a desktop notification from the terminal
tired of switching to the console to check if some command has finished yet? if notify-send does not work on your box try this one... e.g. rsync -av -e /usr/bin/lsh $HOME slowconnection.bar:/mnt/backup ; z (now fire up X, do something useful, get notified if this stuff has finished).

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

Split video files using avconv along keyframes

Clean up after a poorly-formed tar file
These days, most software distributed in tar files will just contain a directory at the top level, but some tar files don't have this and can leave you with a mess of files in the current folder if you blindly execute $ tar zxvf something.tar.gz This command can help you clean up after such a mistake. However, note that this has the potential to do bad things if someone has been *really* nasty with filenames.


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