The mail command, available in most of the Unix, Linux and Macs, can be used to send the status message right from your bash script so that you always know about your script’s activity.

In this article I am going to share some simple but important tricks on sending mail form shell script. Proper use of these tricks will increase the accountability of your scripts and let you relax at your work.

Simple shell script to send one line status mail.

#!/bin/bash
echo "Message Body!" | /usr/bin/mail -s "Message Title" example@example.com

What if you want to send a multi-line message? you can wrap your lines in a shell function and use the following code.

#!/bin/bash
function mystatus {
    echo "Script started successfully"
    echo "Backup operation completed successfully"
    echo "File transferred successfully"
}
mystatus | /usr/bin/mail -s "Message Title" example@example.com

Alternatively you can store messages in a temporary file and load the message body from the file

#!/bin/bash

TMPFILE="/tmp/mailbody.txt"
echo "Script started successfully" > $TMPFILE
echo "Backup operation completed successfully" >> $TMPFILE
echo "File transferred successfully" >> $TMPFILE

/usr/bin/mail -s "Message Title" example@example.com < $TMPFILE

A real example: how you can get the status email whether your MySQL database is backed up properly or not.

#!/bin./bash
function mysqlbackup {
    echo "Script started successfully"
    if (mysqldump -uusername -ppassword database_name > data.sql); then
        echo "MySQL database backed up successfully"
    else
        echo "Error: Could not take database backup!"
    fi

}
mysqlbackup | /usr/bin/mail -s "Backup Status" example@example.com

For more details about bash scripting read this Advance Bash-Scripting Guide.

Hope this simple  script will be helpful for you. Please let us know your feedback.

First you need to create a table in MySQL Database to store the image data. Log into you database and run the following sql command:
CREATE TABLE  `images` (
`id` int(11) NOT NULL auto_increment,
`name` varchar(100) default NULL,
`size` int(11) default NULL,
`type` varchar(20) default NULL,
`content` mediumblob,
PRIMARY KEY  (`id`)
) ENGINE=MyISAM;

Once the table have been created, we are ready to write codes. Now create a folder in you webserver named rayImg and create image.php and upload.php files inside the folder.

Open the image.php, copy and paste the following code and save it.

File: image.php

<?php
	/**
	 * Display image form database
	 *
	 * Retrive an image from mysql database if image id is provided.
	 *
	 * @example to display a image with image id 1, place <img src="image.php?id=1" > in your html file.
	 *
	 * @author Md. Rayhan Chowdhury
	 * @copyright www.raynux.com
	 * @license LGPL
	 */

	// verify request id.
	if (empty($_GET['id']) || !is_numeric($_GET['id'])) {
		echo 'A valid image file id is required to display the image file.';
		exit;
	}

	$imageId = $_GET['id'];

	//connect to mysql database
	if ($conn = mysqli_connect('localhost', 'root', 'root', 'test')) {
		$content = mysqli_real_escape_string($conn, $content);
		$sql = "SELECT type, content FROM images where id = {$imageId}";

		if ($rs = mysqli_query($conn, $sql)) {
			$imageData = mysqli_fetch_array($rs, MYSQLI_ASSOC);
			mysqli_free_result($rs);
		} else {
			echo "Error: Could not get data from mysql database. Please try again.";
		}
		//close mysqli connection
		mysqli_close($conn);

	} else {
		echo "Error: Could not connect to mysql database. Please try again.";
	}	

	if (!empty($imageData)) {
		// show the image.
		header("Content-type: {$imageData['type']}");
		echo $imageData['content'];
	}
?>

Now open the update.php, copy and paste the following code and save it.

File: upload.php

<?php
/**
 * Upload an image to mysql database.
 *
 *
 *
 * @author Md. Rayhan Chowdhury
 * @copyright www.raynux.com
 * @license LGPL
 */

// Check for post data.
if ($_POST && !empty($_FILES)) {
	$formOk = true;

	//Assign Variables
	$path = $_FILES['image']['tmp_name'];
	$name = $_FILES['image']['name'];
	$size = $_FILES['image']['size'];
	$type = $_FILES['image']['type'];

	if ($_FILES['image']['error'] || !is_uploaded_file($path)) {
		$formOk = false;
		echo "Error: Error in uploading file. Please try again.";
	}

	//check file extension
	if ($formOk && !in_array($type, array('image/png', 'image/x-png', 'image/jpeg', 'image/pjpeg', 'image/gif'))) {
		$formOk = false;
		echo "Error: Unsupported file extension. Supported extensions are JPG / PNG.";
	}
	// check for file size.
	if ($formOk && filesize($path) > 500000) {
		$formOk = false;
		echo "Error: File size must be less than 500 KB.";
	}

	if ($formOk) {
		// read file contents
		$content = file_get_contents($path);

		//connect to mysql database
		if ($conn = mysqli_connect('localhost', 'root', 'root', 'test')) {
			$content = mysqli_real_escape_string($conn, $content);
			$sql = "insert into images (name, size, type, content) values ('{$name}', '{$size}', '{$type}', '{$content}')";

			if (mysqli_query($conn, $sql)) {
				$uploadOk = true;
				$imageId = mysqli_insert_id($conn);
			} else {
				echo "Error: Could not save the data to mysql database. Please try again.";
			}

			mysqli_close($conn);
		} else {
			echo "Error: Could not connect to mysql database. Please try again.";
		}
	}
}
?>

<html>
	<head>
		<title>Upload image to mysql database.</title>
		<style type="text/css">
			img{
				margin: .2em;
				border: 1px solid #555;
				padding: .2em;
				vertical-align: top;
			}
		</style>
	</head>
	<body>
		<?php if (!empty($uploadOk)): ?>
			<div>
		  		<h3>Image Uploaded:</h3>
		  	</div>
			<div>
				<img src="image.php?id=<?=$imageId ?>" width="150px">
				<strong>Embed</strong>: <input size="25" value='<img src="image.php?id=<?=$imageId ?>">'>
			</div>

			<hr>
		<? endif; ?>

		<form action="<?=$_SERVER['PHP_SELF']?>" method="post" enctype="multipart/form-data" >
		  <div>
		  	<h3>Image Upload:</h3>
		  </div>
		  <div>
		  	<label>Image</label>
		  	<input type="hidden" name="MAX_FILE_SIZE" value="500000">
			<input type="file" name="image" />
		    <input name="submit" type="submit" value="Upload">
		  </div>
		</form>
	</body>
</html>

Replace line

mysqli_connect(‘localhost’, ‘root’, ‘root’, ‘test’)

with

mysqli_connect(‘your host’, ‘your username’, ‘your password’, ‘your database name’)

in both the file and save again.

You are done. Open upload.php from your browser and upload you desired image and view the uploaded image.