The following scripts were run for /bin/bash, version 4.0.33, and then comes their outputs. In the second example seems to have a warning: "binary operator expected". Why the error is generated? and why there is no error for the first example? ---------------------------------- var1="word1 word2" echo $var1 if (test -z "\"$var1\"") then echo "first" else echo second fi
word1 word2 second ---------------------------------- var1="word1 word2" echo $var1 if (test -z ""$var1"") then echo "first" else echo second fi word1 word2 ./ss1: line 3: test: word1: binary operator expected second ----------------------------------
