Print asterisk instead of password (Bash) Post: 302989766

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Top Forums Shell Programming and Scripting Print asterisk instead of password (Bash) Post 302989766 by rbatte1 on Wednesday 18th of January 2017 05:32:55 AM

01-18-2017

Moderator

I think that the -p flag of read takes the next item as a prompt, so you might have:-

Code:

$ cat pass.sh
echo "Enter the username"
read username

stty -echo
read -p "Enter password:- " password
stty echo
echo           # Force new-line because otherwise
               # the cursor is left at the end of the prompt and may confuse any subsequent output.

To display one * for every key press will be more tricky. You would need to read the input 1 character at a time and display the *, building up your overall password variable as you go. No doubt you would also want to handle mistakes in the input, so you would have to allow a backspace character and both delete an * from the screen (making sure that you don't start deleting the prompt) but also remove the last character from the variable you are building up.

Is it really worth this much effort? A telnet or ssh login prompt does not go to these lengths, and it's of limited value to the user anyway.

Those horrible project management phrases are clanging in my head - cost justification; business need; supportability; ..........

Robin

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droplang

DROPLANG(1)						  PostgreSQL 9.2.7 Documentation					       DROPLANG(1)

NAME

       droplang - remove a PostgreSQL procedural language

SYNOPSIS

       droplang [connection-option...] langname [dbname]

       droplang [connection-option...] --list | -l  [dbname]

DESCRIPTION

       droplang is a utility for removing an existing procedural language from a PostgreSQL database.

       droplang is just a wrapper around the DROP EXTENSION (DROP_EXTENSION(7)) SQL command.

	   Caution
	   droplang is deprecated and may be removed in a future PostgreSQL release. Direct use of the DROP EXTENSION command is recommended
	   instead.

OPTIONS

       droplang accepts the following command line arguments:

       langname
	   Specifies the name of the procedural language to be removed. (This name is lower-cased.)

       [-d] dbname, [--dbname=]dbname
	   Specifies from which database the language should be removed. The default is to use the database with the same name as the current
	   system user.

       -e, --echo
	   Display SQL commands as they are executed.

       -l, --list
	   Show a list of already installed languages in the target database.

       -V, --version
	   Print the droplang version and exit.

       -?, --help
	   Show help about droplang command line arguments, and exit.

       droplang also accepts the following command line arguments for connection parameters:

       -h host, --host=host
	   Specifies the host name of the machine on which the server is running. If host begins with a slash, it is used as the directory for the
	   Unix domain socket.

       -p port, --port=port
	   Specifies the Internet TCP/IP port or local Unix domain socket file extension on which the server is listening for connections.

       -U username, --username=username
	   User name to connect as.

       -w, --no-password
	   Never issue a password prompt. If the server requires password authentication and a password is not available by other means such as a
	   .pgpass file, the connection attempt will fail. This option can be useful in batch jobs and scripts where no user is present to enter a
	   password.

       -W, --password
	   Force droplang to prompt for a password before connecting to a database.

	   This option is never essential, since droplang will automatically prompt for a password if the server demands password authentication.
	   However, droplang will waste a connection attempt finding out that the server wants a password. In some cases it is worth typing -W to
	   avoid the extra connection attempt.

ENVIRONMENT

       PGDATABASE, PGHOST, PGPORT, PGUSER
	   Default connection parameters

       This utility, like most other PostgreSQL utilities, also uses the environment variables supported by libpq (see Section 31.14, "Environment
       Variables", in the documentation).

DIAGNOSTICS

       Most error messages are self-explanatory. If not, run droplang with the --echo option and see under the respective SQL command for details.
       Also, any default connection settings and environment variables used by the libpq front-end library will apply.

NOTES

       Use createlang(1) to add a language.

EXAMPLES

       To remove the language pltcl:

	   $ droplang pltcl dbname

SEE ALSO

       createlang(1), DROP EXTENSION (DROP_EXTENSION(7)), DROP LANGUAGE (DROP_LANGUAGE(7))

PostgreSQL 9.2.7						    2014-02-17							       DROPLANG(1)