'\"
'\" Copyright (c) 1993 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: global.n,v 1.6 2004/05/17 22:23:42 dkf Exp $
'\" 
.so man.macros
.TH global n "" Tcl "Tcl Built-In Commands"
.BS
'\" Note:  do not modify the .SH NAME line immediately below!
.SH NAME
global \- Access global variables
.SH SYNOPSIS
\fBglobal \fIvarname \fR?\fIvarname ...\fR?
.BE

.SH DESCRIPTION
.PP
This command is ignored unless a Tcl procedure is being interpreted.
If so then it declares the given \fIvarname\fR's to be global variables
rather than local ones.
Global variables are variables in the global namespace.
For the duration of the current procedure
(and only while executing in the current procedure),
any reference to any of the \fIvarname\fRs
will refer to the global variable by the same name.
.PP
\fIvarname\fR is always treated as the name of a variable, not an
array element.  An error is returned if the name looks like an array element,
such as \fBa(b)\fR.
.SH EXAMPLE
This procedure accumulates the strings passed to it in a global
buffer, separated by newlines.  It is useful for situations when you
want to build a message piece-by-piece (as if with \fBputs\fR) but
send that full message in a single piece (e.g. over a connection
opened with \fBsocket\fR or as part of a counted HTTP response).
.CS
proc accum {string} {
    global accumulator
    append accumulator $string \\n
}
.CE

.SH "SEE ALSO"
namespace(n), upvar(n), variable(n)

.SH KEYWORDS
global, namespace, procedure, variable