retrieve the contents of a selection

## NAME

Tk_GetSelection - retrieve the contents of a selection

## SYNOPSIS

#include <tk.h>

int Tk_GetSelection(interp, tkwin, selection, target, proc, clientData)

## ARGUMENTS

`Tcl_Interp *interp` (in)
  Interpreter to use for reporting errors.
`Tk_Window tkwin` (in)
  Window on whose behalf to retrieve the selection (determines display from which to retrieve).
`Atom selection` (in)
  The name of the selection to be retrieved.
`Atom target` (in)
  Form in which to retrieve selection.
`Tk_GetSelProc *proc` (in)
  Procedure to invoke to process pieces of the selection as they are retrieved.
`ClientData clientData` (in)
  Arbitrary one-word value to pass to proc.

## DESCRIPTION

Tk_GetSelection retrieves the selection specified by the atom selection in the format specified by target. The selection may actually be retrieved in several pieces; as each piece is retrieved, proc is called to process the piece. Proc should have arguments and result that match the type Tk_GetSelProc:
typedef int Tk_GetSelProc( ClientData clientData, Tcl_Interp *interp, char *portion);
The clientData and interp parameters to proc will be copies of the corresponding arguments to Tk_GetSelection. Portion will be a pointer to a string containing part or all of the selection. For large selections, proc will be called several times with successive portions of the selection. The X Inter-Client Communication Conventions Manual allows a selection to be returned in formats other than strings, e.g. as an array of atoms or integers. If this happens, Tk converts the selection back into a string before calling proc. If a selection is returned as an array of atoms, Tk converts it to a string containing the atom names separated by white space. For any other format besides string, Tk converts a selection to a string containing hexadecimal values separated by white space.

Tk_GetSelection returns to its caller when the selection has been completely retrieved and processed by proc, or when a fatal error has occurred (e.g. the selection owner didn't respond promptly). Tk_GetSelection normally returns TCL_OK; if an error occurs, it returns TCL_ERROR and leaves an error message in interp->result. Proc should also return either TCL_OK or TCL_ERROR. If proc encounters an error in dealing with the selection, it should leave an error message in interp->result and return TCL_ERROR; this will abort the selection retrieval.

## KEYWORDS

format, get, selection retrieval