How to read a character at a time from STDIN without needing topress return key?

[Kenneth McDonald]

In the following bit of code:

print STDIN.getc
STDOUT.flush

The code for whatever key I type isn't actually printed out until I go
on to hit the return key. How can I have it printed as soon as I type
a character key?

Thanks,
Ken

 

[Nobuyoshi Nakada]

Hi,

At Thu, 4 Sep 2008 05:40:43 +0900,
Kenneth McDonald wrote in [ruby-talk:313786]:

In the following bit of code:

print STDIN.getc
STDOUT.flush

The code for whatever key I type isn't actually printed out until I go
on to hit the return key. How can I have it printed as soon as I type
a character key?

With io-console, you can do:

print STDIN.getch

http://www.rubyist.net/~nobu/ruby/io-console.tar.bz2
http://www.rubyist.net/~nobu/ruby/io-console-0.2.gem

 

[Bertram Scharpf]

Hi,

Am Donnerstag, 04. Sep 2008, 05:40:43 +0900 schrieb Kenneth McDonald:

In the following bit of code:

print STDIN.getc
STDOUT.flush

The code for whatever key I type isn't actually printed out until I go on
to hit the return key. How can I have it printed as soon as I type a
character key?

On feasible operating systems you can install the "termios" gem.
Then say something like:

class IO
def nocanon
term = Termios::getattr self
term.c_lflag &= ~Termios::ICANON
Termios::setattr self, Termios::TCSANOW, term
yield
ensure
term.c_lflag |= Termios::ICANON
Termios::setattr self, Termios::TCSANOW, term
end
end

$stdin.nocanon do
c = $stdin.getc
end

Maybe you like to have a look at how I let the user enter
passwords: <http://bertram-scharpf.homelinux.com/src/password.rb>.

Good luck!

Bertram

 

[James Gray]

In the following bit of code:

print STDIN.getc
STDOUT.flush

The code for whatever key I type isn't actually printed out until I
go on to hit the return key. How can I have it printed as soon as I
type a character key?

http://blog.grayproductions.net/articles/i_just_want_one_character

Hope that helps.

James Edward Gray II