Commands using tail (292)

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small CPU benchmark with PI, bc and time.
$ # 4 cores with 2500 pi digits $ CPUBENCH 4 2500 $. $ every core will use 100% cpu and you can see how fast they calculate it. $ if you do 50000 digitits and more it can take hours or days

Mute speakers after an hour
Mutes the speakers after an hour, in case you fall asleep watching a video...

Tail a log and replace according to a sed pattern
Tails a log and replaces it line-by-line according to whatever you want to replace. Useful if the file writing to the log can't be modified, so you need to modify its output instead.

Detect illegal access to kernel space, potentially useful for Meltdown detection
Based on capsule8 agent examples, not rigorously tested

Cut the first 'N' characters of a line
Saves one character, the original is probably clearer

delete a line from your shell history
If you're a moron like me, sometimes your fingers get away from you and you, for example, enter your password when you're already authenticated to ssh-agent, sudo, etc., and your password ends up in shell history. Here's how to get it out.

Monitor a file's size

cpu stress test
For each cpu set mask and then monitor your cpu infos. Temp,load avg. etc. For example for 2nd cpu or 2nd core taskset 0x00000002 yes > /dev/null & For example for 3rd cpu or 3rd core taskset 0x00000004 yes > /dev/null & For example for 4th cpu or 4th core taskset 0x00000008 yes > /dev/null & Monitor your cpu temp with this command if you want watch -n1 "acpi -t" Load avg. from top command top kerim@bayner.com http://www.bayner.com/

Reboot machine when everything is hanging
If the machine is hanging and the only help would be the power button, this key-combination will help to reboot your machine (more or less) gracefully. R - gives back control of the keyboard S - issues a sync E - sends all processes but init the term singal I - sends all processes but init the kill signal U - mounts all filesystem ro to prevent a fsck at reboot B - reboots the system Save your file before trying this out, this will reboot your machine without warning! http://en.wikipedia.org/wiki/Magic_SysRq_key

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"


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