Using /proc for gathering information
/proc is an in-memory pseudo filesystem available with the GNU/Linux operating system. It was actually introduced to provide an interface to read several system parameters from the user space. It is very interesting and we can gather lots of information from it. Let's see how to.
How to do it...
If you look at /proc, you will see several files and directories, some of which are already explained in other recipes in this chapter. You can simply cat files in /proc and the subdirectories to get information. All of them are well-formatted text.
There will be a directory in /proc for every process that is running on the system, named after the PID of that process.
Suppose Bash is running with PID 4295 (pgrep bash), /proc/4295 will exist. Each of the directories corresponding to the process will contain a lot of information regarding to that process. Few of the important files in /proc/PID are as follows.
environ: This contains environment variables associated...