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How do I get one key from the terminal at a time, under POSIX?

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How do I get one key from the terminal at a time, under POSIX?

    #!/usr/bin/perl -w
    use strict;
    $| = 1;
    for (1..4) {
        my $got;
        print "gimme: ";
        $got = getone();
        print "--> $got\n";

    BEGIN {
        use POSIX qw(:termios_h);

        my ($term, $oterm, $echo, $noecho, $fd_stdin);

        $fd_stdin = fileno(STDIN);

        $term     = POSIX::Termios->new();
        $oterm     = $term->getlflag();

        $echo     = ECHO | ECHOK | ICANON;
        $noecho   = $oterm & ~$echo;

        sub cbreak {
            $term->setcc(VTIME, 1);
            $term->setattr($fd_stdin, TCSANOW);

        sub cooked {
            $term->setcc(VTIME, 0);
            $term->setattr($fd_stdin, TCSANOW);

        sub getone {
            my $key = '';
            sysread(STDIN, $key, 1);
            return $key;

    END { cooked() }

Source: Perl FAQ: System Interaction
Copyright: Copyright (c) 1997 Tom Christiansen and Nathan Torkington.
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