Greetings everyone,

I would like to understand the entries in my /etc/wpa_supplicant/wpa_supplicant.conf

ctrl_interface=/var/run/wpa_supplicant
ctrl_interface_group=0

When I go to /var/run/wpa_supplicant there's a file called wlan0

[root@localhost wpa_supplicant]# ls -la
total 8
drwxr-x---. 2 root root 4096 Apr 17 19:00 .
drwxr-xr-x. 24 root root 4096 Apr 17 20:08 ..
srwxrwx---. 1 root root 0 Apr 17 19:00 wlan0
[root@localhost wpa_supplicant]#

The wlan0 is a symbolic link to another file. I would like to know where this file is. When I do a cat wlan0 I receive the message:

[root@localhost wpa_supplicant]# cat wlan0
cat: wlan0: No such device or address

I'm aware of the readlink command but it doesn't display anything useful. I spoke with a co-worker and he said that it's a file where the sockets are defined.

I plan to format my computer and reconfigure my wireless card, post all the steps here and maybe make a YouTube video so others can learn from my experience. So far it has been an adventure trying to get my wireless to work under CentOS 6.4. I got it to work but with the help of others. I'm finding a lot of information about the wpa_supplicant.conf file but not about /var/run/wpa_supplicant/wlan0 file. I need to be able to recreate it. Thanks in advance for your valuable input.

Your co-worker is right, this is a socket file and not a symbolic link (you have the s instead of the l in the ls long listing).

Don't worry about the creation of this file. They are special files created by the program with some system calls, but I don't think you can create one from userspace. But I know that a named pipe (fifo) can be created with the mkfifo command.