Felipe Cruz

PHP function to check valid email addresses

Below you will find a small useful function on PHP that uses regular expressions to find out if a provided email address has a valid format or not.

<?PHP

function correctemail($emailtocheck) {

    if (! preg_match( '/^[A-Za-z0-9!#$%&\'*+-/=?^_`{|}~]+@[A-Za-z0-9-]+(\.[A-Za-z0-9-]+)+[A-Za-z]$/', $emailtocheck)) {

            return false;

    } else {

        return true;

    }

}

?>

The script wont check for valid domains but for RFC compliant type addresses, all in all you could combine this function with one that checks if a provided domain under an email is valid and that should do the trick.

An UFO on my picture?

On my last set of pictures taken on the Tuberculosis Hospital in Prusia, Cartago, Costa Rica I was checking if the Sigma 24-70mm HSM was showing any signs of vignetting, for this reason I started zooming on the corners of one of the pictures and then found this:

 

Now, I have to say im no ufologist but you have to admit it seems weird.

A 400% loupe on the object in question:

If anyone is interested in the original picture at high resolution you can download it from here:

DOWNLOAD ORIGINAL UFO PICTURE

You need to look the right top area of the picture, use the crop below as a guide of where to look, the object appears above an electrical pole.

All in all, this was an interesting detail to find on a picture, I showed it to several people already and the reactions are interesting, they are sure its an UFO. This in combination with the kind of spooky/mystical place where this photo was taken surely helps your mind roll along with the idea of an UFO.

All I know ... we will never know =)

Comments are welcome

Doing a manual disk format on Mac OS X

I found that the disk utility that is usually used while formatting hard drives works most of the times but has certain issues when you are trying to format Drives that have an existing windows partition. I havent been able to really pin point the issue, but in those cases the only way to format the drive is doing a manual format.

So ... how do you format a drive manually on Mac OS?

First of all, you need to have root access and need to do a sudo:

type

sudo sh

Then press ENTER ( you will get a prompt for the root password, go ahead)

Once you do that, then you will probably need to get a list of the available drives on the system.

type

diskutil list

Then press ENTER (you will get something similar to the image below)

Basically the command will give you a listing of all your drives, take note of the NAME of the drive you want to format which will be needed on the final and most important step.

Ok, so now you have the name of the drive you want to format, I suppose I dont need to warn you about what you are trying to do, any information stored on the drive will be completely wiped out and you will have a fresh clean new drive.

You are supposed to be under sudo to run the command.

The format command is:

diskutil eraseDisk "Journaled HFS+" name disk3

(where disk3 is the name of the drive you want to format)

Thats all =)

Felipe

Prusia Tuberculosis Hospital & Irazu Volcano with D700 & Sigma 24-70mm

On my last photography blog I said I would be making more tests on the Sigma 24-70mm with the new HSM motor on my new Nikon D700.

Although the test in itself is mostly focused on the lens, I have to mention the fact that the Nikon D700 is simply superb!, the color quality and detail even on higuer ISO's is simply amazing, the camera is super responsive, you just hear that huge CLICK!!! and voila!

So far I think the Sigma 24-70mm is a smart buy, im very happy with the results, sharpness on the lens is amazing, vignetting almost not visible in most pictures i've taken or simply minimal. All in all I will not jump into technical details since I dont have the proper background for that, but I will show you some of the pictures taken which I think show great color and detail.

Buy Sigma 24-70mm f/2.8 HSM directly from Amazon Here (You can find both Nikon & Canon versions)

You can click on each picture to see a bigger version

 

Image taken on Irazu Volcano in Costa Rica, settings: Aperture f/7.1, Shutter Speed 1/250, ISO 200, Focal Length 38mm on Sigma 24-70mm HSM. No Post processing, image came like this from the camera.

Example number 2

Picture taken on the Prusia Tuberculosis Hospital (Sanatorio), Image details: Aperture f/5.6, Shutter Speed 1/2000, ISO 200, Focal Length 24mm. Post processing: used dodge and burn on the sky to make it show a darker blue.

Example 3

 

Picture taken on the Prusia Tuberculosis Hospital, image details: Aperture f/5.6, Shutter speed 1/2000, ISO 200, Focal Length 24mm. Post processing: None, picture came like this from the camera, the D700 has been set to take pictures in VIVID.

Example 4

Picture taken on the inside of the abandoned Tuberculosis Hospital in Prusia ( Cartago, Costa Rica), picture details: Aperture f/4.5, Shutter Speed 1/15, ISO 360, Focal Length 24mm, No post processing.

Example 5

Image taken on the Prusia Tuberculosis Hospital (Cartago, Costa Rica), image details: Aperture f/9, Shutte Speed 1/400, ISO 200, Focal Length 24mm

All in all I think that images speak for themselves, if you are interested on the Sigma 24-70mm these might give you a good idea. I think the lens is great, sharp, super fast, fast focusing, it simply works like a charm on the top of the line Nikon D700.

Im very glad I bought it instead of the Nikkor 24-70mm

All pictures have been taken using the VIVID setting on the Nikon D700, I love rich colors on pictures, I think they simply look better, but thats my taste.

I will probably bring more Sigma 24-70mm HSM examples in the near future.

By the way if you are interested about the Prusia abandoned Hospital, you can find a little more information on the link below:

http://www.costaricapages.com/blog/tico/spooky-haunts/1601

Some say its a haunted place =)

So long

Felipe

Null routes in Linux

A null route basically specifies the network service of linux to redirect all traffic from an specific host to a 'pit hole', 'black hole' or to be more accurate NULL.

Why is this useful?

Basically its a fast way to block a host or network from your box, all traffic from the host will be pretty much sent to the garbage immediately.

How to do it?

This is done by adding the following line to the /etc/sysconfig/static-routes file:

any host 111.111.111.111 reject

(being 111.111.111.111 the ip address to block)

After you add all the ip addresses or networks you want to block, simply restart your network services and the new null route will be added.

When you perform a "route -n" command you will see this IP with "-" as it's gateway. This will cause your server to drop all response traffic to this IP.

Destination Gateway Genmask Flags Metric Ref Use Iface
111.111.111.111 - 255.255.255.255 !H 0 - 0 -

If you wish to un-blacklist this IP in the future simply remove the aforementioned line from the static-routes file and restart the "network" service on the server.

As a webhosting provider in Costa Rica, i've used this simple tweak many many times on our servers for certain unwanted traffic. Hope you find it as useful as I did.

Felipe

Using Awk and Bash to create a network mapper

Below you will find a simple script made with awk and bash to create network maps.

The script basically needs to know the base ip address and the range of ips to explore and it will try to ping every single ip. If an ip address is alive then it will be added to the map file.

The script generates a mapfile.txt archive with the resulting network map.

Its useful either to understand how you can use the powerful awk with bash scripting or simply as a network tool.

The Script Below:

# - IP MAPPER BY FELIPE CRUZ
baseip="10.0.0."
range=256 # - Number of ips to trace
cont=1
echo "Starting Mapping Process, this may take a while ..."
echo "MAP FILE will be saves in ./mapfile.txt"
while [ $cont -lt $range ]; do

        res=`ping -c 1 -W 1 $baseip$cont | sed '1d'| awk '{printf "%1-s",$6}'`
        #echo $res     
        process=` echo $res | awk -F"=" '{printf "%1-s",$1}'`
        if [ "$process" ==  "ttl" ]; then
                echo "IP $baseip$cont IS ALIVE!"
                echo "IP $baseip$cont IS ALIVE" >> ./mapfile.txt
        fi
        let cont=cont+1
done

Bash Script for FTP uploads / backups

The following is a fully functional backup script programmed fully on Bash

As you know bash can be a little picky with certain spaces, so please try and not change the script much unless you know what you are doing.
You need to create a file with the source below and give execution permissions.

For example:
touch script.sh

then add the source code with VI or any editor and finally

chmod a+x script.sh

You are free to use the script, in combination with the crontab you can automate you server to upload any specific files or folders you might need to back up to a remote ftp server. I currently use this same script on multiple servers with great success.

I would appreciate you leaving my name on the Script ( ego talking )

The Script Below:

# =====================================
# SCRIPT by Felipe Cruz for SHDaemon.com
# please respect the reference above
# =====================================

# -- CONFIGURE VALUES --
ftpserv="10.0.0.1"    # - Ftp server ip
ftpusr="ftpuser"        # - ftp user
ftppass="mypass"  # - ftp password
remotefolder=""       # - remote storage location
localfolder="/home/myfiles"  # - where are my files

# -- DO NOT CHANGE FROM DOWN BELOW --

recorrido=`ls $localfolder`

for i in $recorrido; do

        echo "Copying archive $i , proceso $$ , use CTRL+C to abort "
        echo "Information:"
        echo `file $localfolder/$i`
# -- Comandos FTP --
ftp -i -v -n $ftpserv <<ENDFTP
user $ftpusr $ftppass
binary

send $localfolder/$i $remotefolder/$i
bye
ENDFTP

        echo "Completed upload for $i"
        echo ""
        sleep 3

done

echo "FINISHED"

First Shots Sigma 24-70mm and Nikon D700

This is one of the first image captures with my new Nikon D700 combined with the Sigma 24-70mm HSM lens.

First of all I have to say that im not a professional photographer neither a "gadget" analyzer but I actually googled a lot of information on the new sigma 24-70mm before I decided to go for it.

The Sigma 24-70mm is considered to be one of the few (if any) professional grade lenses to compete with the Nikkor more expensive options.

I bought mine from Amazon at $900, the Nikkor 24-70mm is listed at Amazon at an usual price of $1,899.

Since I just recently jumped into the FX (full frame) world, I needed a viable option to avoid spending $1,899 on a new lens since my DX Lenses will really not work as desired on my new Nikon D700.

Check out another Sigma 24-70mm HSM picture below

The picture on the right was taken with an ISO 200, focal length 24mm, shutter speed 1/320, aperture at f/3.2.

Honestly i've taken a few pictures using the lens, but I think the lens is extremely sharp. The colors on the pictures shown have not been retouched whatsoever, I just chose Vivid saturation on the D700 settings.

Love the contrast and colors.

So far my first impressions of the Sigma 24-70mm are super good, the lens is super sharp, the auto focusing is super silent and fast on my Nikon D700. There are some minor issues on front focusing when using a higher focal length of 70mm but nothing annoying.

Some people don't like the fact that the lens is an 82 mm diameter lens, obviously buying a b+w filter for such a lens is expensive, but I love the feeling of the lens, is huge!, I love heavy lens and cameras cause its easier for me to take decent pictures without a tripod.

Ill probably will be taking quite a few more shots on the next few days on the new Sigma 24-70mm HSM and will post more examples.

Last example

Focal length 46mm

Iso 200

Aperture f/5

Shutter speed 1/30

Check my latest review and examples on the Sigma 24-70mm HSM here!