Commands using cat (514)

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Print current running shell, PID
works as well as echo $0, but also prints process id, which pts you're using. echo $SHELL doesn't always get updated when changing shells, so this is a better solution than that. Just one more variation on a theme.

Outputs files with ascii art in the intended form.
Files containing ascii art (e.g. with .nfo extension) are typically not correctly reproduced at the command line when using cat. With iconv one can easily write a wrapper to solve this: $ #!/bin/bash $ if [ -z "$@" ]; then echo "Usage: $(basename $0) file [file] ..." $ else iconv -f437 -tutf8 "$@"; fi $ exit 0

print multiplication formulas
seq -s ' ' 1 9 | sed -n ':a;p;s/ *\w$//;h;/^$/t;b a;q' | tac | awk '{for(i=1;i

Watch the size of a directory using figlet
You can substitute /home/$USER with any path you like.

Find usb device in realtime
Using this command you can track a moment when usb device was attached.

Be notified about overheating of your CPU and/or motherboard
You'll be notified if your core 1 temperature exceeds 50 degrees, you can change the monitored device by editing the "Core 1" or change the critical temperature by editing the "-gt 50" part. Note: you must have lm-sensors installed and configured in order to get this command working.

Equivalent to ifconfig -a in HPUX

Synchronize date and time with a server over ssh
If you are stuck behind a firewall and want to synchronize time with another server but you do not want to port forward NTP (which uses UDP) then this command is handy. It gets the time from a server and sets the local time. It is not that accurate but I can live with a second or so drift.

Detect encoding of a text file
This command gives you the charset of a text file, which would be handy if you have no idea of the encoding.

Print macOS current power delivery max wattage
Print the max wattage of the current power draw source for a Mac. Note that the current amount of watts drawn may be lower, particularly if a high-wattage adapter is plugged into a Mac that has a full battery.


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