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

ping MAC ADDRESS
# first install arp-scan if not have it arp-scan 10.1.1.0/24 .... show ip+mac in localnet awk '/00:1b:11:dc:a9:65/ {print $1}' .... get ip associated with MAC ` backtick make do command substitution passing ip to command ping

Suspend to ram

sleep for 1/10s or 1/100s or even 1/1000000s
sleep in microseconds instead of seconds Alternatively to usleep, which is not defined in POSIX 2008 (though it was defined up to POSIX 2004, and it is evidently available on Linux and other platforms with a history of POSIX compliance), the POSIX 2008 standard defines nanosleep

Find the package that installed a command

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.

Show display adapter, available drivers, and driver in use

Check executable shared library usage
provides list of shared libraries required by executable

Create QR codes from a URL.
QR codes are those funny square 2d bar codes that everyone seems to be pointing their smart phones at. Try the following... $ qrurl http://xkcd.com Then open qr.*.png in your favorite image viewer. Point your the bar code reader on your smart phone at the code, and you'll shortly be reading xkcd on your phone. URLs are not the only thing that can be encoded by QR codes... short texts (to around 2K) can be encoded this way, although this function doesn't do any URL encoding, so unless you want to do that by hand it won't be useful for that.

Search $PATH for a command or something similar
Searches your $PATH for whatever you substitute for bash, though not sure if this will work if you substitute a different shell for bash!


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