Commands by Eun (1)

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Resolution of a image
You can use the -format switch to get the size of the image. Replace "logo:" with your image.

check open ports without netstat or lsof

Comma insertions
Insert a comma where necessary when counting large numbers. I needed to separate huge amounts of packets and after 12+ hours of looking in a terminal, I wanted it in readable form.

Make a server's console beep when the network is down
This is like ping -a, but it does the opposite. It alerts you if the network is down, not up. Note that the beep will be from the speaker on the server, not from your terminal. Once a second, this script checks if the Internet is accessible and beeps if it is not. I define the Net as being "UP", if I can ping Google's public DNS server (8.8.8.8), but of course you could pick a different static IP address. I redirect the beep to /dev/console so that I can run this in the background from /etc/rc.local. Of course, doing that requires that the script is run by a UID or GID that has write permissions to /dev/console (usually only root). Question: I am not sure if the -W1 flag works under BSD. I have only tested this under GNU/Linux using ping from iputils. If anybody knows how portable -W is, please post a comment.

cd up a number of levels
Instead of typing "cd ../../.." you can type ".. 3". For extremely lazy typists, you can add this alias: alias ...=".. 2" ....=".. 3" - so now you can write just .... !!! NB the .. function needs to be "source"d or included in your startup scripts, perhaps .bashrc.

Check if x86 Solaris based system is 32bit or 64bit
This is likely only valid on Solaris based systems. Unfortunately a lot of the more universal techniques for determining if a system is 32bit or 64bit on x86 solaris fail to give much more information than "i86pc"

stop windows update
Windows only: stops windows update and the nagging restart window. You need your admin password for this one.

take execution time of several commands
The last ; is important. example: time { rm -rf /folder/bar && mkdir -p /folder/bar ; echo "done" ; } command is a bash builtin

Install pip with Proxy
Installs pip packages defining a proxy

Deal with dot files safely


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