'\" '\" Copyright (c) 1996-1997 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: BoolObj.3,v 1.2 2001/09/14 01:42:06 zlaski Exp $ '\" .so man.macros .TH Tcl_BooleanObj 3 8.0 Tcl "Tcl Library Procedures" .BS .SH NAME Tcl_NewBooleanObj, Tcl_SetBooleanObj, Tcl_GetBooleanFromObj \- manipulate Tcl objects as boolean values .SH SYNOPSIS .nf \fB#include <tcl.h>\fR .sp Tcl_Obj * \fBTcl_NewBooleanObj\fR(\fIboolValue\fR) .sp \fBTcl_SetBooleanObj\fR(\fIobjPtr, boolValue\fR) .sp int \fBTcl_GetBooleanFromObj\fR(\fIinterp, objPtr, boolPtr\fR) .SH ARGUMENTS .AS Tcl_Interp *interp .AP int boolValue in Integer value used to initialize or set a boolean object. If the integer is nonzero, the boolean object is set to 1; otherwise the boolean object is set to 0. .AP Tcl_Obj *objPtr in/out For \fBTcl_SetBooleanObj\fR, this points to the object to be converted to boolean type. For \fBTcl_GetBooleanFromObj\fR, this refers to the object from which to get a boolean value; if \fIobjPtr\fR does not already point to a boolean object, an attempt will be made to convert it to one. .AP Tcl_Interp *interp in/out If an error occurs during conversion, an error message is left in the interpreter's result object unless \fIinterp\fR is NULL. .AP int *boolPtr out Points to place where \fBTcl_GetBooleanFromObj\fR stores the boolean value (0 or 1) obtained from \fIobjPtr\fR. .BE .SH DESCRIPTION .PP These procedures are used to create, modify, and read boolean Tcl objects from C code. \fBTcl_NewBooleanObj\fR and \fBTcl_SetBooleanObj\fR will create a new object of boolean type or modify an existing object to have boolean type. Both of these procedures set the object to have the boolean value (0 or 1) specified by \fIboolValue\fR; if \fIboolValue\fR is nonzero, the object is set to 1, otherwise to 0. \fBTcl_NewBooleanObj\fR returns a pointer to a newly created object with reference count zero. Both procedures set the object's type to be boolean and assign the boolean value to the object's internal representation \fIlongValue\fR member. \fBTcl_SetBooleanObj\fR invalidates any old string representation and, if the object is not already a boolean object, frees any old internal representation. .PP \fBTcl_GetBooleanFromObj\fR attempts to return a boolean value from the Tcl object \fIobjPtr\fR. If the object is not already a boolean object, it will attempt to convert it to one. If an error occurs during conversion, it returns \fBTCL_ERROR\fR and leaves an error message in the interpreter's result object unless \fIinterp\fR is NULL. Otherwise, \fBTcl_GetBooleanFromObj\fR returns \fBTCL_OK\fR and stores the boolean value in the address given by \fIboolPtr\fR. If the object is not already a boolean object, the conversion will free any old internal representation. .SH "SEE ALSO" Tcl_NewObj, Tcl_DecrRefCount, Tcl_IncrRefCount, Tcl_GetObjResult .SH KEYWORDS boolean, boolean object, boolean type, internal representation, object, object type, string representation