Bash Scripting

Shell scripting for automation and system administration.

Quick Start

#!/bin/bash
set -euo pipefail

echo "Starting VM provisioning..."

Key Patterns

# Variables
VM_NAME="${VM_NAME:-default}"
MEMORY="${MEMORY:-2048}"

# Conditionals
if [[ -f "$disk_image" ]]; then
    echo "Disk exists"
fi

# Loops
for vm in vm1 vm2 vm3; do
    start_vm "$vm"
done

# Functions
create_disk() {
    local name="$1"
    local size="$2"
    qemu-img create -f qcow2 "${name}.qcow2" "$size"
}

# Arrays
ARGS=(-m 2048 -smp 2 -enable-kvm)
qemu-system-x86_64 "${ARGS[@]}"

Error Handling

set -e  # exit on error
trap 'cleanup' EXIT

command -v qemu-system-x86_64 >/dev/null || { echo "QEMU required"; exit 1; }