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Smart renaming
A powerfull way to rename file using sed groups. & stand for the matched expression. \1 referes to the first group between parenthesis. \2 to the second.

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

List processes playing sound
When trying to play a sound you may sometimes get an error saying that your sound card is already used, but not by what process. This will list all processes playing sound, useful to kill processes that you no longer need but that keep using your sound card.

Search for an active process without catching the search-process
This does the same thing as many of the 'grep' based alternatives but allows a more finite control over the output. For example if you only wanted the process ID you could change the command: $ ps -ef | awk '/mingetty/ && !/awk/ {print $2}' If you wanted to kill the returned PID's: $ ps -ef | awk '/mingetty/ && !/awk/ {print $2}' | xargs -i kill {}

Use a Gmail virtual disk (GmailFS) on Ubuntu
Packages: gmailfs fuse-utils libfuse2 gvfs-fuse Config files: /etc/gmailfs/gmailfs.conf; ~/.gmailfs.conf (make a copy from the another one) Unmount: $ fusermount -u /mount/path/ /etc/fstab (Optional): none /mount/path/ gmailfs noauto,user[,username=USERNAME,password=PASSWORD,fsname=VOLUME] 0 0 NOTES: - The options between [] are optional since they already setuped on the config files. - The '-p' flag shows a prompt for the password entry. - It's necessary to add the user to the 'fuse' group. You can do that with: $ sudo chgrp fuse /dev/fuse and $ sudo usermod -a -G fuse USER - The volume name is not needed but highly recommended to avoid file corruption. Also choose a non-trivial name. - Google doesn't approve the use of Gmail account other than e-mail purposes. So, I recommend the creation of a new account for this.

Print stack trace of a core file without needing to enter gdb interactively
The pstack command prints a stack trace of running processes without needing to attach a debugger, but what about core files? The answer, of course, is to use this command. Usage: gdbbt program corefile

rsync Command that limits bandwidth
Useful for transferring large file over a network during operational hours

Find usb device
I often use it to find recently added ou removed device, or using find in /dev, or anything similar. Just run the command, plug the device, and wait to see him and only him

Compose 2 images to 1
Compose 2 images (foreground.jpg with background.jpg) into 1 (image.jpg), the numeric parameters stablish the size of the foreground.jpg image (96x96) and the position x,y (+250+70) relative to the background.jpg image. Images can be any format, jpg, png, bmp, etc...

Convert CSV to JSON
Replace 'csv_file.csv' with your filename.


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