2 files changed, 14 insertions, 5 deletions
diff --git a/tools/install.sh b/tools/install.sh
index c83a6f23d..1586cdee5 100755
--- a/tools/install.sh
+++ b/tools/install.sh
@@ -1,5 +1,12 @@
 set -e
 
+CHECK_ZSH_INSTALLED=$(grep /zsh$ /etc/shells | wc -l)
+if [ ! $CHECK_ZSH_INSTALLED -ge 1 ]; then
+  echo "\033[0;33m Zsh is not installed!\033[0m Please install zsh first!"
+  exit
+fi
+unset CHECK_ZSH_INSTALLED
+
 if [ ! -n "$ZSH" ]; then
   ZSH=~/.oh-my-zsh
 fi
@@ -23,14 +30,16 @@ fi
 
 echo "\033[0;34mUsing the Oh My Zsh template file and adding it to ~/.zshrc\033[0m"
 cp $ZSH/templates/zshrc.zsh-template ~/.zshrc
-sed -i -e "/^export ZSH=/ c\\
+sed "/^export ZSH=/ c\\
 export ZSH=$ZSH
-" ~/.zshrc
+" ~/.zshrc > ~/.zshrc-omztemp
+mv -f ~/.zshrc-omztemp ~/.zshrc
 
 echo "\033[0;34mCopying your current PATH and adding it to the end of ~/.zshrc for you.\033[0m"
-sed -i -e "/export PATH=/ c\\
+sed "/export PATH=/ c\\
 export PATH=\"$PATH\"
-" ~/.zshrc
+" ~/.zshrc > ~/.zshrc-omztemp
+mv -f ~/.zshrc-omztemp ~/.zshrc
 
 TEST_CURRENT_SHELL=$(expr "$SHELL" : '.*/\(.*\)')
 if [ "$TEST_CURRENT_SHELL" != "zsh" ]; then
diff --git a/tools/upgrade.sh b/tools/upgrade.sh
index 5f0a81f1d..e06e4f331 100644
--- a/tools/upgrade.sh
+++ b/tools/upgrade.sh
@@ -9,7 +9,7 @@ then
   printf '\033[0;32m%s\033[0m\n' '\____/_/ /_/  /_/ /_/ /_/\__, /    /___/____/_/ /_/  '
   printf '\033[0;32m%s\033[0m\n' '                        /____/                       '
   printf '\033[0;34m%s\033[0m\n' 'Hooray! Oh My Zsh has been updated and/or is at the current version.'
-  printf '\033[0;34m%s\033[1m%s\033[0m\n' 'To keep up on the latest news and updates, follow us on twitter: ' 'http://twitter.com/ohmyzsh'
+  printf '\033[0;34m%s\033[1m%s\033[0m\n' 'To keep up on the latest news and updates, follow us on twitter: ' 'https://twitter.com/ohmyzsh'
   printf '\033[0;34m%s\033[1m%s\033[0m\n' 'Get your Oh My Zsh swag at: ' 'http://shop.planetargon.com/'
 else
   printf '\033[0;31m%s\033[0m\n' 'There was an error updating. Try again later?'