How do you create a directory in shell scripting?

In shell scripts, creating directories primarily uses the mkdir command. Below are the basic methods and several practical examples:

Basic Usage

The simplest command to create a directory is:

bash
mkdir new_directory

This creates a new directory named new_directory in the current working directory.

Creating Multiple Directories

You can create multiple directories at once:

bash
mkdir dir1 dir2 dir3

Creating Nested Directories

If you need to create multi-level directories, you can use the -p option:

bash
mkdir -p dir1/dir2/dir3

This creates dir1, then dir2 within dir1, and finally dir3 within dir2. If parent directories already exist, the -p option will ignore them.

Example: Creating User Data Directories

Suppose you are writing a script that needs to create personal folders for multiple users under /data/users. You can write the script as follows:

bash
#!/bin/bash

# Assuming the user list is stored in an array
users=("alice" "bob" "charlie")

# Create the base directory
base_dir="/data/users"
mkdir -p "$base_dir"

# Create directories for each user
for user in "${users[@]}"; do
  mkdir "$base_dir/$user"
-done

This script first ensures the base directory /data/users exists, then iterates over each username in the array to create individual directories.

Error Handling

When creating directories, you may encounter permission issues or other errors. Check the exit status of the mkdir command to handle errors:

bash
mkdir new_directory
if [ $? -ne 0 ]; then
  echo "Failed to create directory."
  exit 1
fi

This covers the basic methods and common use cases for creating directories in shell scripts. We hope these examples help you understand how to apply these commands in practical work.