Simple shell script to check whether a website is down only for me or everyone else. Uses curl and isup.me service.

isitme.sh

# Simple script to figure out whether a site is up or not

TOOL_SITE="http://www.isup.me/"

if [ $# -ne 1 ]
then
  echo "Incorrect arguments specified"
  exit 1
fi

# Check if curl is installed, if not exit
dpkg -s curl | grep "install ok installed" 1>/dev/null
if [ $? -ne 0 ]
then
  echo "curl is not installed. Install via 'sudo apt-get install curl'"
  exit 1
fi

# Make an HTTP request to our tool site
# grep for "It's just you... <site> is up"
curl "$TOOL_SITE$1" 2>/dev/null | grep "just you.*is up" 1>/dev/null
if [ $? -eq 0 ]
then
  echo "$1 is up"
else
  echo "$1 is down"
fi

Hey, you can skip the grep at line 12 and probably at line 21.

$ dpkg -s curl
dpkg-query: package 'curl' is not installed and no information is available
Use dpkg --info (= dpkg-deb --info) to examine archive files.

$ echo $?
1