<HTML><HEAD><TITLE>Built-In Commands - set manual page</TITLE></HEAD><BODY> <H3><A NAME="M2">NAME</A></H3> set - Read and write variables <H3><A NAME="M3">SYNOPSIS</A></H3> <B>set </B><I>varName </I>?<I>value</I>?<BR> <H3><A NAME="M4">DESCRIPTION</A></H3> Returns the value of variable <I>varName</I>. If <I>value</I> is specified, then set the value of <I>varName</I> to <I>value</I>, creating a new variable if one doesn't already exist, and return its value. If <I>varName</I> contains an open parenthesis and ends with a close parenthesis, then it refers to an array element: the characters before the first open parenthesis are the name of the array, and the characters between the parentheses are the index within the array. Otherwise <I>varName</I> refers to a scalar variable. Normally, <I>varName</I> is unqualified (does not include the names of any containing namespaces), and the variable of that name in the current namespace is read or written. If <I>varName</I> includes namespace qualifiers (in the array name if it refers to an array element), the variable in the specified namespace is read or written. <P> If no procedure is active, then <I>varName</I> refers to a namespace variable (global variable if the current namespace is the global namespace). If a procedure is active, then <I>varName</I> refers to a parameter or local variable of the procedure unless the <B><A HREF="../TkCmd/global.htm">global</A></B> command was invoked to declare <I>varName</I> to be global, or unless a <B><A HREF="../TkCmd/variable.htm">variable</A></B> command was invoked to declare <I>varName</I> to be a namespace variable. <H3><A NAME="M5">SEE ALSO</A></H3> <B><A HREF="../TkCmd/expr.htm">expr</A></B>, <B><A HREF="../TkCmd/proc.htm">proc</A></B>, <B><A HREF="../TkCmd/trace.htm">trace</A></B>, <B><A HREF="../TkCmd/unset.htm">unset</A></B> <H3><A NAME="M6">KEYWORDS</A></H3> <A href="../Keywords/R.htm#read">read</A>, <A href="../Keywords/W.htm#write">write</A>, <A href="../Keywords/V.htm#variable">variable</A> <HR><PRE> <A HREF="../copyright.htm">Copyright</A> © 1993 The Regents of the University of California. <A HREF="../copyright.htm">Copyright</A> © 1994-1996 Sun Microsystems, Inc. <A HREF="../copyright.htm">Copyright</A> © 1995-1997 Roger E. Critchlow Jr.</PRE> </BODY></HTML>