When automating file operations like ls, cp, and mv, proper error handling is crucial. Many scripts fail silently, leaving administrators unaware of issues until they cause bigger problems. Implementing email alerts for both successes and failures creates a robust monitoring system.

We'll use these Bash features:

|| (OR operator) for error handling

&& (AND operator) for success tracking

$? to check exit status

mail command for notifications

#!/bin/bash

# Configuration
RECIPIENT="admin@example.com"
SUBJECT_PREFIX="[File Ops]"
TMP_LOG=$(mktemp)

# Function to send email
send_alert() {
    local status=$1
    local message=$2
    
    echo "$message" | mail -s "$SUBJECT_PREFIX $status" "$RECIPIENT"
    rm -f "$TMP_LOG"
}

# Main operations
{
    ls /target/directory || {
        send_alert "FAILED" "ls command failed on /target/directory"
        exit 1
    }
    
    cp source.txt /destination/ && \
    mv oldfile.txt newfile.txt || {
        send_alert "FAILED" "File operations failed. Check script execution."
        exit 1
    }
    
} > "$TMP_LOG" 2>&1

# If we reach here, all commands succeeded
send_alert "SUCCESS" "All file operations completed successfully"

For more complex scripts, consider this pattern:

#!/bin/bash

# Enhanced logging function
log() {
    echo "[$(date '+%Y-%m-%d %H:%M:%S')] $1" >> /var/log/file_ops.log
}

# Operation wrapper
safe_operation() {
    "$@" >> "$TMP_LOG" 2>&1
    if [ $? -ne 0 ]; then
        log "ERROR: Command failed: $*"
        send_alert "FAILED" "Command failed: $*\n\n$(cat "$TMP_LOG")"
        exit 1
    fi
    log "SUCCESS: $*"
}

# Usage example
safe_operation ls -l /target
safe_operation cp -v source.txt /backups/
safe_operation mv data.tmp data.final

For systems without mail command:

# Using curl for Slack/webhook notifications
send_slack_alert() {
    local message="$1"
    curl -X POST -H 'Content-type: application/json' \
    --data "{\"text\":\"$message\"}" \
    https://hooks.slack.com/services/your/webhook/url
}

# Using SSMTP as mail alternative
send_ssmtp_alert() {
    {
        echo "To: $RECIPIENT"
        echo "Subject: $1"
        echo ""
        echo "$2"
    } | ssmtp "$RECIPIENT"
}

In Bash, every command returns an exit status (0 for success, non-zero for failure). We can check this using $? immediately after command execution:

#!/bin/bash

ls /nonexistent/directory
if [ $? -ne 0 ]; then
    echo "Error: ls command failed"
    # Add email alert logic here
fi

For cleaner code, use trap to catch errors throughout the script:

#!/bin/bash

# Set trap for ERR signal
trap 'handle_error $LINENO' ERR

handle_error() {
    local line=$1
    echo "Error occurred on line $line"
    # Send email notification
    echo "Script failed at $(date)" | mail -s "Script Failure" admin@example.com
    exit 1
}

# Your operations
ls /some/directory
cp source.txt destination/
mv oldname newname

# Success notification
echo "Script completed successfully at $(date)" | mail -s "Script Success" admin@example.com

Here's a production-ready script with comprehensive error handling:

#!/bin/bash

# Configuration
TO_EMAIL="admin@example.com"
LOG_FILE="/var/log/script_operations.log"

# Log and email function
notify() {
    local message="$1"
    local subject="$2"
    
    echo "$(date '+%Y-%m-%d %H:%M:%S') - $message" >> "$LOG_FILE"
    echo "$message" | mail -s "$subject" "$TO_EMAIL"
}

# Error handler
error_exit() {
    notify "Script failed at line $1" "CRITICAL: File Operation Failed"
    exit 1
}

trap 'error_exit $LINENO' ERR

# Main operations
notify "Starting file operations" "Script Started"

ls /target/directory || exit 1
cp -v source.txt /target/destination/ >> "$LOG_FILE"
mv -v /target/destination/source.txt /target/destination/renamed.txt >> "$LOG_FILE"

# Success
notify "All operations completed successfully" "SUCCESS: File Operations Complete"

For more complex scripts, consider these approaches:

# Set strict mode
set -euo pipefail

# Function to execute commands with logging
safe_exec() {
    local cmd="$@"
    if ! $cmd >> "$LOG_FILE" 2>&1; then
        notify "Command failed: $cmd" "Command Failure"
        return 1
    fi
}

# Usage
safe_exec cp largefile.dat /backup/
safe_exec mv /backup/largefile.dat /backup/archive/