Starting the Shell
The GNU bash shell is a program that provides interactive access to the Linux system. It runs as a regular program and is normally started whenever a user logs in to a terminal. The shell that the system starts depends on your user ID configuration.
The /etc/passwd
file contains a list of all the system user accounts, along with some basic configuration information about each user. Here's a sample entry from a /etc/passwd
file:
christine:x:501:501:Christine Bresnahan:/home/christine:/bin/bash
Each entry has seven data fields, with fields separated by colons. The system uses the data in these fields to assign specific features for the user. Most of these entries are discussed in more detail in Chapter 7. For now, just pay attention to the last field, which specifies the user's shell program.