ref: d3d1b3b47ff80f451c6c9f8b7f1262fef6545f2b
dir: /man/9/variable/
.TH VARIABLE 9 .SH NAME variable \- interrogate a button variable .SH SYNOPSIS \f5variable \fIvar\fR ?\fIvalue\fR? .SH DESCRIPTION .B Variable queries or sets the value of a Tk radiobutton, checkbutton or choicebutton variable. An error diagnostic will be returned if the variable is of the wrong type (if for instance it is the name of a named channel). .PP If \fIvalue\fR is given, the value of the variable is set to that value, and any associated buttons will subsequently reflect this in their appearance. Omitting the \fIvalue\fR argument returns the current value of the variable. .PP The special variable .B lasterror holds the text of the last Tk error encountered. It resets when queried. .SH SEE ALSO .IR checkbutton (9), .IR choicebutton (9), .IR radiobutton (9)