NAME

       clipboard - Manipulate Tk clipboard

SYNOPSIS

       clipboard option ?arg arg ...?
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DESCRIPTION

       This  command  provides  a  Tcl interface to the Tk clipboard, which stores data for later
       retrieval using the selection mechanism (via the -selection CLIPBOARD option).   In  order
       to copy data into the clipboard, clipboard clear must be called, followed by a sequence of
       one or more  calls  to  clipboard  append.   To  ensure  that  the  clipboard  is  updated
       atomically, all appends should be completed before returning to the event loop.

       The first argument to clipboard determines the format of the rest of the arguments and the
       behavior of the command.  The following forms are currently supported:

       clipboard clear ?-displayof window?
              Claims ownership of the clipboard on window's  display  and  removes  any  previous
              contents.  Window defaults to “.”.  Returns an empty string.

       clipboard append ?-displayof window? ?-format format? ?-type type? ?--? data
              Appends  data  to  the clipboard on window's display in the form given by type with
              the representation given by  format  and  claims  ownership  of  the  clipboard  on
              window's display.

              Type  specifies  the  form  in  which  the selection is to be returned (the desired
              “target” for conversion, in ICCCM terminology), and should be an atom name such  as
              STRING  or  FILE_NAME;  see  the  Inter-Client Communication Conventions Manual for
              complete details.  Type defaults to STRING.

              The format argument specifies the representation that should be  used  to  transmit
              the  selection  to  the  requester (the second column of Table 2 of the ICCCM), and
              defaults to STRING.  If format is STRING, the selection  is  transmitted  as  8-bit
              ASCII  characters.   If  format  is  ATOM,  then  the  data  is divided into fields
              separated by white space; each field is converted to its atom value, and the 32-bit
              atom value is transmitted instead of the atom name.  For any other format,  data is
              divided into fields separated by white space and  each  field  is  converted  to  a
              32-bit  integer;  an  array  of integers is transmitted to the selection requester.
              Note that strings passed to clipboard append are concatenated before conversion, so
              the  caller  must take care to ensure appropriate spacing across string boundaries.
              All items appended to the clipboard with the same type must have the same format.

              The format argument is needed only for compatibility with clipboard requesters that
              do not use Tk.  If the Tk toolkit is being used to retrieve the CLIPBOARD selection
              then the value is converted back to a string at the requesting end,  so  format  is
              irrelevant.

              A  -- argument may be specified to mark the end of options:  the next argument will
              always be used as data.  This feature may  be  convenient  if,  for  example,  data
              starts with a -.

       clipboard get ?-displayof window? ?-type type?
              Retrieve  data  from  the  clipboard  on window's display.  Window defaults to “.”.
              Type specifies the form in which the data is to be returned and should be  an  atom
              name  such  as  STRING  or  FILE_NAME.   Type  defaults to STRING.  This command is
              equivalent to “selection get -selection CLIPBOARD”.

              Note that on modern X11 systems, the most useful type to retrieve  for  transferred
              strings is not STRING, but rather UTF8_STRING.

EXAMPLES

       Get the current contents of the clipboard.
              if {[catch {clipboard get} contents]} {
                  # There were no clipboard contents at all
              }

       Set the clipboard to contain a fixed string.
              clipboard clear
              clipboard append "some fixed string"

       You  can  put  custom  data into the clipboard by using a custom -type option. This is not
       necessarily portable, but can be very useful. The method of passing Tcl scripts  this  way
       is effective, but should be mixed with safe interpreters in production code.
              # This is a very simple canvas serializer;
              # it produces a script that recreates the item(s) when executed
              proc getItemConfig {canvas tag} {
                 set script {}
                 foreach item [$canvas find withtag $tag] {
                    append script {$canvas create } [$canvas type $item]
                    append script { } [$canvas coords $item] { }
                    foreach config [$canvas itemconf $item] {
                       lassign $config name - - - value
                       append script [list $name $value] { }
                    }
                    append script \n
                 }
                 return [string trim $script]
              }

              # Set up a binding on a canvas to cut and paste an item
              set c [canvas .c]
              pack $c
              $c create text 150 30 -text "cut and paste me"
              bind $c <<Cut>> {
                 clipboard clear
                 clipboard append -type TkCanvasItem \
                       [getItemConfig %W current]
                 # Delete because this is cut, not copy.
                 %W delete current
              }
              bind $c <<Paste>> {
                 catch {
                    set canvas %W
                    eval [clipboard get -type TkCanvasItem]
                 }
              }

SEE ALSO

       interp(3tcl), selection(3tk)

KEYWORDS

       clear, format, clipboard, append, selection, type