Commands by prayer (26)

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Encrypted archive with openssl and tar
Create an AES256 encrypted and compressed tar archive. User is prompted to enter the password. Decrypt with: $ openssl enc -d -aes256 -in | tar --extract --file - --gzip

Link a deep tree of files all into on directory
If you want to pull all of the files from a tree that has mixed files and directories containing files, this will link them all into a single directory. Beware of filesystem files-per-directory limits.

List all groups and the user names that were in each group
"cut" the user names from /etc/passwd and then running a loop over them.

Silently ensures that a FS is mounted on the given mount point (checks if it's OK, otherwise unmount, create dir and mount)
In my example, the mount point is /media/mpdr1 and the FS is /dev/sdd1 /mountpoint-path = /media/mpdr1 filesystem=/dev/sdd1 Why this command ? Well, in fact, with some external devices I used to face some issues : during data transfer from the device to the internal drive, some errors occurred and the device was unmounted and remounted again in a different folder. In such situations, the command mountpoint gave a positive result even if the FS wasn't properly mounted, that's why I added the df part. And if the device is not properly mounted, the command tries to unmount, to create the folder (if it exists already it will also work) and finally mount the FS on the given mount point.

Video Google download
Download google video with wget. Or, if you wish, pass video URL to ie mplayer to view as stream. 1. VURL: replace with url. I.e. http://video.google.com/videoplay?docid=12312312312312313# 2. OUPUT_FILE : optionally change to a more suited name. This is the downloaded file. I.e. foo.flv # Improvements greatly appreciated. (close to my first linux command after ls -A :) ) Breakedown pipe by pipe: 1. wget: html from google, pass to stdout 2. grep: get the video url until thumbnailUrl (not needed) 3. grep: Strip off everything before http:// 4. sed: urldecode 5. echo: hex escapes 6. sed: stipr of tailing before thumbnailUrl 7. wget: download. Here one could use i.e. mplayer or other...

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

Rename files in batch

Text graphing ping output filter
Nasty perl one-liner that provides a sparkline of ping times. If you want a different history than the last 30, just put that value in. It (ab)uses unicode to draw the bars, inspired by https://github.com/joemiller/spark-ping . It's not the most bug-free piece of code, but what it lacks in robustness it makes up for in capability. :) If anyone has any ideas on how to make it more compact or better, I'd love to hear them. I included a ping to google in the command just as an example (and burned up 10 chars doing it!). You should use it with: $ ping example.com | $SPARKLINE_PING_COMMAND

Burn CD/DVD from an iso, eject disc when finished.
cdrecord -scanbus will tell you the (x,y,z) value of your cdr (for example, mine is 3,0,0)

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


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