Bash- if clause doesn't work correctly -

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i want make shutdown script , doesn't work intended. wrote.

echo "wanna shutdown (y/n)?"   read answer  if [ $answer=="y" ]              sudo shutdown -p else      printf "something...."

whatever press shuts down. why?

you need put spaces around == operator. otherwise test expression single word, , non-empty words test successfully.

in addition, if wish portable, should use = instead of ==. , wise double quote variable expansions because [ won't you.

if [ "$answer" = y ];

on other hand, if using bash (or ksh or zsh) use more forgiving [[ conditional expression:

if [[ $answer = y ]];

TSQL