NAME
Net::VNC - A simple VNC client
SYNOPSIS
use Net::VNC;
my $vnc = Net::VNC->new({hostname => $hostname, password => $password});
$vnc->depth(24);
$vnc->login;
print $vnc->name . ": " . $vnc->width . ' x ' . $vnc->height . "\n";
my $image = $vnc->capture;
$image->save("out.png");DESCRIPTION
Virtual Network Computing (VNC) is a desktop sharing system which uses the RFB (Remote FrameBuffer) protocol to remotely control another computer. This module acts as a VNC client and communicates to a VNC server using the RFB protocol, allowing you to capture the screen of the remote computer.
This module dies upon connection errors (with a timeout of 15 seconds) and protocol errors.
This implementation is based largely on the RFB Protocol Specification, http://www.realvnc.com/docs/rfbproto.pdf. That document has an error in the DES encryption description, which is clarified via http://www.vidarholen.net/contents/junk/vnc.html.
METHODS
new
The constructor. Given a hostname and a password returns a Net::VNC object:
my $vnc = Net::VNC->new({hostname => $hostname, password => $password});Optionally, you can also specify a port, which defaults to 5900. For ARD (Apple Remote Desktop) authentication you must also specify a username. You must also install Crypt::GCrypt::MPI and Crypt::Random.
login
Logs into the remote computer:
$vnc->login;name
Returns the name of the remote computer:
print $vnc->name . ": " . $vnc->width . ' x ' . $vnc->height . "\n";width
Returns the width of the remote screen:
print $vnc->name . ": " . $vnc->width . ' x ' . $vnc->height . "\n";height
Returns the height of the remote screen:
print $vnc->name . ": " . $vnc->width . ' x ' . $vnc->height . "\n";capture
Captures the screen of the remote computer, returning an Image::Imlib2 object:
my $image = $vnc->capture;
$image->save("out.png");You may call capture() multiple times. Each time, the $image buffer is overwritten with the updated screen. So, to create a series of ten screen shots:
for my $n (1..10) {
my $filename = sprintf 'snapshot%02d.png', $n++;
$vnc->capture()->save($filename);
print "Wrote $filename\n";
}depth
Specify the bit depth for the screen. The supported choices are 24, 16 or 8. If unspecified, the server's default value is used. This property should be set before the call to login().
save_bandwidth
Accepts a boolean, defaults to false. Specifies whether to use more CPU-intensive algorithms to compress the VNC datastream. LAN or localhost connections may prefer to leave this false. This property should be set before the call to login().
list_encodings
Returns a list of encoding number/encoding name pairs. This can be used as a class method like so:
my %encodings = Net::VNC->list_encodings();send_key_event_down
Send a key down event. The keys are the same as the corresponding ASCII value. Other common keys:
BackSpace 0xff08
Tab 0xff09
Return or Enter 0xff0d
Escape 0xff1b
Insert 0xff63
Delete 0xffff
Home 0xff50
End 0xff57
Page Up 0xff55
Page Down 0xff56
Left 0xff51
Up 0xff52
Right 0xff53
Down 0xff54
F1 0xffbe
F2 0xffbf
F3 0xffc0
F4 0xffc1
... ...
F12 0xffc9
Shift (left) 0xffe1
Shift (right) 0xffe2
Control (left) 0xffe3
Control (right) 0xffe4
Meta (left) 0xffe7
Meta (right) 0xffe8
Alt (left) 0xffe9
Alt (right) 0xffea
$vnc->send_key_event_down('A');send_key_event_up
Send a key up event:
$vnc->send_key_event_up('A');send_key_event
Send a key down event followed by a key up event:
$vnc->send_key_event('A');send_key_event_string
Send key events for every character in a string:
$vnc->send_key_event_string('Hello');send_pointer_event( $button_mask, $x, $y )
Send pointer event (usually a mouse). This is used to move the pointer or make clicks or drags.
It is easier to call the mouse_move or <mouse_click> methods instead.
mouse_move_to($x, $y)
Send the pointer to the given position. The cursor instantly jumps there instead of smoothly moving to there.
mouse_click
Click on current pointer position.
mouse_right_click
Right-click on current pointer position.
BUGS AND LIMITATIONS
Bit depth
We do not yet support 8-bit true-colour mode, which is commonly supported by servers but is rarely employed by clients.
Byte order
We have currently tested this package against servers with the same byte order as the client. This might break with a little-endian server/big-endian client or vice versa. We're working on tests for those latter cases. Testing and patching help would be appreciated.
Efficiency
We've implemented a subset of the data compression algorithms supported by most VNC servers. We hope to add more of the high-compression transfer encodings in the future.
AUTHORS
Leon Brocard acme@astray.com
Chris Dolan clotho@cpan.org
Apple Remote Desktop authentication based on LibVNCServer
Maurice Castro maurice@ipexchange.com.au
Many thanks for Foxtons Ltd for giving Leon the opportunity to write the original version of this module.
Copyright (C) 2006, Leon Brocard
This module is free software; you can redistribute it or modify it under the same terms as Perl itself.