SHELL SCRIPT TO ACCEPT USERNAME AS COMMAND LINE ARGUMENTS AND CHECK THE USER LOGIN IN OR NOT

ACCEPT USERNAME AS COMMAND LINE ARGUMENTS  AND CHECK    THE USER LOGIN IN OR NOT

 echo "To check the user login or not"

if [ $# -eq 1 ]

then

who > y.txt

c=`grep -n $1 y.txt | wc -l`

fi

if [ $c -gt 0 ]

then

echo "The user has login"

else

echo "The user has not login"

fi

OUTPUT:

 [@localhost ~]$ sh acceptlogin.sh 2k7ca320

To check the user login or not

The user has login

[@localhost ~]$ sh acceptlogin.sh 2k7ca337

To check the user login or not

The user has not login

[@localhost ~]$