Commands by decept (3)

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Big Countdown Clock with hours, minutes and seconds
Figlet is easy to find for download on the internet, and works for any text. Quite cool.

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.

Which processes are listening on a specific port (e.g. port 80)
swap out "80" for your port of interest. Can use port number or named ports e.g. "http"

finding cr-lf files aka dos files with ^M characters
its useful to run dos2unix command later on them.

Convert all files for iPhone with HandbrakeCLI

Recover remote tar backup with ssh
Here how to recover the remote backup over ssh

Bind a key with a command
the -x option is for binding to a shell command

Shows cpu load in percent
Show the current load of the CPU as a percentage. Read the load from /proc/loadavg and convert it using sed: Strip everything after the first whitespace: $ sed -e 's/ .*//' Delete the decimal point: $ sed -e 's/\.//' Remove leading zeroes: $ sed -e 's/^0*//'

Make a ready-only filesystem ?writeable? by unionfs
First look into /etc/modules if you have unionfs (or squashfs) support. If not, add the modules. UnionFS combines two filesystems. If there is a need to write a file, /tmp/unioncache will be used to write files (first create that directory). Reads will be done where the file is found first. http://tldp.org/HOWTO/SquashFS-HOWTO/creatingandusing.html

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