4.2.Document-practice-for-http-ver-1.txt

command1 && command2

which httpd &>/dev/null && echo "httpd is installed on this host"

if command1
then
   command2
fi

if which httpd &>/dev/null
then
   echo "httpd is installed on this host"
fi

which httpd &>/dev/null
httpd_status=$?

if [[ $httpd_status -eq 0 ]]
then
  echo "httpd is installed on this host"
fi

-----------------------------
command1 && command2 || command3
which httpd &>/dev/null && echo "httpd is installed on this host" || echo "httpd is not installed"

if command1
then
   command2
   command3
else
   command4
   command5
fi


if which httpd &>/dev/null
then
  echo "httpd is installed on this host"

else
  echo "httpd is not installed"
fi
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