Introduction to bash

bash is a standard Linux shell. You can use bash to execute Linux commands.

# Execute Linux command with bash
ls

Let's check the environment variables. You can check it with the env command.

env

When combined with grep, you can retrieve only the environment variables you need.

# Get only those that contain PATH
env | grep PATH

Use the export command to set environment variables.

export EnvironmentVariableName=EnvironmentVariableValue

Examples:

export LANG=en_US.utf8

The bash configuration file is ".bashrc" in your home directory.

~/.bashrc

There is also a special config file called ".bash_profile", but use ".bashrc" for normal configs.

If you write the above environment variable settings in ".bashrc", they can be set automatically when the shell is loaded.

Let's create a bash shell script. This is useful when executing frequently used Linux commands.

Suppose you save the following script as "myecho".

#!/bin/bash

echo 'Hello'

Save this script and change the permissions to 755 with the chmod command so you can run it

chmod 755 myecho

execution

./myecho

Shebang is "#!/bin/bash".

Bash is the standard shell script on Linux, but there are other shell scripts such as csh, ksh, and zsh.

Shell scripts are like dialects, and each Linux OS has a different standard shell.

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