How to (GUI) prompt for password from bash?

I remember there was a gnome only command that we could insert in a bash script to mount a Linux disk that would pop up a little window to grab a password.

I know there are bash commands to read a string but they are not GUIs and they echo the characters typed. This gnome command popped up a window and echoed the key strokes with "*"'s.

Can someone remind of me of the name of that gnome command that pops up a password GUI? Does it have counterparts for other windows managers (besides gnome) and Cygwin?

These days I'm running Cygwin bash under windows 8. I'm launching the bash scripts from the emacs compile command. These bash scripts run sqlplus (Oracle) and sqlcmd (Microsoft) scripts to create databases and database users and they require passwords be specified on the command line for sqlplus/sqlcmd. I'd like to pop up a little GUI that will prompt for a password. Is there a open source Cygwin/bash friendly GUI that will prompt for a password and insert the results via the bash backquote feature?

Thanks
Siegfrried

The gnome command may have been gsudo, which doesn't return a password as much as check a password.

Since you're using BASH, may I suggest read -s ? That will echo no characters.