View process environment details with proc

The process environment consists of all the individual environment variables which are passed on to the program by the shell when the program is launched. This environment can be read and changed by the program during its execution, and can affect how a program is linked or how it executes. For all these reasons it [...]

Command substitution in BASH

BASH has the ability to execute a command string and replace that string with the output of the command. Or to say it another way, the output of a command will replace the command itself.
There are 2 ways to accomplish this.
The first is to surround the command with backticks or blockquotes.
`command`
You can also substitute with [...]

How to correctly use LD_LIBRARY_PATH

The LD_LIBRARY_PATH environment variable contains a colon separated list of paths that the linker uses to resolve library dependencies of ELF executables at run-time. These paths will be given priority over the standard library paths /lib and /usr/lib. The standard paths will still be searched, but only after the list of paths in LD_LIBRARY_PATH [...]

Customize the BASH PS1 command prompt

The PS1 environment controls the appearance of the BASH command line prompt. There are a variety of default prompts but they usually include username, hostname, and working directory. You can easily customize your prompt to display information important to you as well as add color and style formatting.
Here we can see the default prompt is [...]

Select threading implementation using LD_ASSUME_KERNEL

For backwards compatibility, many Linux distributions support both the older LinuxThreads implementation as well as the newer Native POSIX Thread Library (NPTL). By setting the LD_ASSUME_KERNEL environment variable you can tell the dynamic linker to assume that it is running on top of a particular kernel version. This will override the dynamic linker’s default [...]