Commands by eneko (6)

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Get your X11 screen mode

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"

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.

Socksify any program to avoid restrictive firwalls
Require: - tsocks (deb pkg) - A working SOCKS proxy. It's easy with ssh: $ ssh -N -D localhost:1080 your.home.pc -p 443 - tsocks configuration in your /etc/tsocks.conf (for the previous): server = 127.0.0.1 server_port = 1080

Use Kernighan & Ritchie coding style in C program

Configuring proxy client on terminal without leaving password on screen or in bash_history
Prompts the user for username and password, that are then exported to http_proxy for use by wget, yum etc Default user, webproxy and port are used. Using this script prevent the cleartext user and pass being in your bash_history and on-screen

Is today the last day of the month?
Nice simple example of something we can do in bash.

get some information about the parent process from a given process

reset hosed terminal

create ICO file with more than one image
requires imagemagick. -background transparent is of course optional.


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