If you are working on UNIX platform, this is an easier task. Use optionally echoing of input facility of UNIX. Try this :

printf("Enter word :");
chomp($visible_word =  <STDIN>>);  #### you can see what you are typin
+g ...
printf("\n");

system("stty -echo");
chomp($passwd = <STDIN>);   #### this won't be visible on screen ...
printf("\n");
system("stty echo");
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