/ 
IO-Termios-0.03
River stage one • 6 direct dependents • 7 total dependents
/ IO::Termios

NAME

IO::Termios - supply termios(3) methods to IO::Handle objects

SYNOPSIS

use IO::Termios;

my $term = IO::Termios->open( "/dev/ttyS0", "9600,8,n,1" )
   or die "Cannot open ttyS0 - $!";

$term->print( "Hello world\n" ); # Still an IO::Handle

while( <$term> ) {
   print "A line from ttyS0: $_";
}

DESCRIPTION

This class extends the generic IO::Handle object class by providing methods which access the system's terminal control termios(3) operations.

CONSTRUCTORS

$term = IO::Termios->new()

Construct a new IO::Termios object around the terminal for the program. This is found by checking if any of STDIN, STDOUT or STDERR are a terminal. The first one that's found is used. An error occurs if no terminal can be found by this method.

$term = IO::Termios->new( $handle )

Construct a new IO::Termios object around the given filehandle.

$term = IO::Termios->open( $path, $modestr )

Open the given path, and return a new IO::Termios object around the filehandle. If the open call fails, undef is returned.

If $modestr is provided, the constructor will pass it to the set_mode method before returning.

METHODS

$attrs = $term->getattr

Makes a tcgetattr() call on the underlying filehandle, and returns a IO::Termios::Attrs object.

If the tcgetattr() call fails, undef is returned.

$term->setattr( $attrs )

Makes a tcsetattr() call on the underlying file handle, setting attributes from the given IO::Termios::Attrs object.

If the tcsetattr() call fails, undef is returned. Otherwise, a true value is returned.

FLAG-ACCESSOR METHODS

Theses methods are implemented in terms of the lower level methods, but provide an interface which is more abstract, and easier to re-implement on other non-POSIX systems. These should be used in preference to the lower ones.

For efficiency, when getting or setting a large number of flags, it may be more efficient to call getattr, then operate on the returned object, before possibly passing it to setattr. The returned IO::Termios::Attrs object supports the same methods as documented here.

The following two sections of code are therefore equivalent, though the latter is more efficient as it only calls setattr once.

$term->setbaud( 38400 );
$term->setcsize( 8 );
$term->setparity( 'n' );
$term->setstop( 1 );

my $attrs = $term->getattr;
$attrs->setbaud( 38400 );
$attrs->setcsize( 8 );
$attrs->setparity( 'n' );
$attrs->setstop( 1 );
$term->setattr( $attrs );

However, a convenient shortcut method is provided for the common case of setting the baud rate, character size, parity and stop size all at the same time. This is set_mode:

$term->set_mode( "38400,8,n,1" );

$baud = $term->getibaud

$baud = $term->getobaud

$term->setibaud( $baud )

$term->setobaud( $baud )

$term->setbaud( $baud )

Convenience accessors for the ispeed and ospeed. $baud is an integer directly giving the line rate, instead of one of the Bnnn constants.

$bits = $term->getcsize

$term->setcsize( $bits )

Convenience accessor for the CSIZE bits of c_cflag. $bits is an integer 5 to 8.

$parity = $term->getparity

$term->setparity( $parity )

Convenience accessor for the PARENB and PARODD bits of c_cflag. $parity is n, o or e.

$stop = $term->getstop

$term->setstop( $stop )

Convenience accessor for the CSTOPB bit of c_cflag. $stop is 1 or 2.

$mode = $term->getflag_cread

$term->setflag_cread( $mode )

Accessor for the CREAD bit of the c_cflag. This enables the receiver.

$mode = $term->getflag_hupcl

$term->setflag_hupcl( $mode )

Accessor for the HUPCL bit of the c_cflag. This lowers the modem control lines after the last process closes the device.

$mode = $term->getflag_clocal

$term->setflag_clocal( $mode )

Accessor for the CLOCAL bit of the c_cflag. This controls whether local mode is enabled; which if set, ignores modem control lines.

$mode = $term->getflag_icanon

$term->setflag_icanon( $mode )

Accessor for the ICANON bit of c_lflag. This is called "canonical" mode and controls whether the terminal's line-editing feature will be used to return a whole line (if false), or if individual bytes from keystrokes will be returned as they are available (if true).

$mode = $term->getflag_echo

$term->setflag_echo( $mode )

Accessor for the ECHO bit of c_lflag. This controls whether input characters are echoed back to the terminal.

$term->set_mode( $modestr )

$modestr = $term->get_mode

Accessor for the derived "mode string", which is a comma-joined concatenation of the baud rate, character size, parity mode, and stop size in a format such as

19200,8,n,1

When setting the mode string, trailing components may be omitted meaning their value will not be affected.

TODO

  • Adding more getflag_*/setflag_* convenience wrappers

  • Automatically upgrading STDIN/STDOUT/STDERR if appropriate, given a flag.

    use IO::Termios -upgrade;

STDIN->setflag_echo( 0 );

  • Modem line control, via TCIOM{GET,SET,BIS,BIC}. Annoyingly it doesn't appear this is available without XS code.

SEE ALSO

  • IO::Tty - Import Tty control constants

AUTHOR

Paul Evans <leonerd@leonerd.org.uk>