'\"
'\" Copyright (c) 1990 The Regents of the University of California.
'\" Copyright (c) 1994-1997 Sun Microsystems, Inc.
'\"
'\" See the file "license.terms" for information on usage and redistribution
'\" of this file, and for a DISCLAIMER OF ALL WARRANTIES.
'\" 
'\" RCS: @(#) $Id$
'\" 
.so man.macros
.TH Tk_Name 3 "" Tk "Tk Library Procedures"
.BS
.SH NAME
Tk_Name, Tk_PathName, Tk_NameToWindow \- convert between names and window tokens
.SH SYNOPSIS
.nf
\fB#include <tk.h>\fR
.sp
Tk_Uid
\fBTk_Name\fR(\fItkwin\fR)
.sp
char *
\fBTk_PathName\fR(\fItkwin\fR)
.sp
Tk_Window
\fBTk_NameToWindow\fR(\fIinterp, pathName, tkwin\fR)
.SH ARGUMENTS
.AS Tcl_Interp *pathName
.AP Tk_Window tkwin in
Token for window.
.AP Tcl_Interp *interp out
Interpreter to use for error reporting.
.AP char *pathName in
Character string containing path name of window.
.BE

.SH DESCRIPTION
.PP
Each window managed by Tk has two names, a short name that identifies
a window among children of the same parent, and a path name that
identifies the window uniquely among all the windows belonging to the
same main window.  The path name is used more often in Tk than the
short name;  many commands, like \fBbind\fR, expect path names as
arguments.
.PP
The \fBTk_Name\fR macro returns a window's
short name, which is the same as the \fIname\fR argument
passed to \fBTk_CreateWindow\fR when
the window was created.  The value is returned
as a Tk_Uid, which may be used just like a string pointer but also has
the properties of a unique identifier (see the manual entry for
\fBTk_GetUid\fR for details).
.PP
The \fBTk_PathName\fR macro returns a
hierarchical name for \fItkwin\fR.
Path names have a structure similar to file names in Unix but with
dots between elements instead of slashes:  the main window for
an application has the path name ``.'';  its children have names like
``.a'' and ``.b''; their children have names like ``.a.aa'' and
``.b.bb''; and so on.  A window is considered to be be a child of
another window for naming purposes if the second window was named
as the first window's \fIparent\fR when the first window was created.
This is not always the same as the X window hierarchy.  For
example, a pop-up
is created as a child of the root window, but its logical parent will
usually be a window within the application.
.PP
The procedure \fBTk_NameToWindow\fR returns the token for a window
given its path name (the \fIpathName\fR argument) and another window
belonging to the same main window (\fItkwin\fR).  It normally
returns a token for the named window, but if no such window exists
\fBTk_NameToWindow\fR leaves an error message in \fIinterp->result\fR
and returns NULL.  The \fItkwin\fR argument to \fBTk_NameToWindow\fR
is needed because path names are only unique within a single
application hierarchy.  If, for example, a single process has opened
two main windows, each will have a separate naming hierarchy and the
same path name might appear in each of the hierarchies.  Normally
\fItkwin\fR is the main window of the desired hierarchy, but this
need not be the case:  any window in the desired hierarchy may be used.

.SH KEYWORDS
name, path name, token, window