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diff --git a/doc/SetOptions.3 b/doc/SetOptions.3 new file mode 100644 index 0000000..a734395 --- /dev/null +++ b/doc/SetOptions.3 @@ -0,0 +1,502 @@ +'\" +'\" Copyright (c) 1998 Sun Microsystems, Inc. +'\" +'\" See the file "license.terms" for information on usage and redistribution +'\" of this file, and for a DISCLAIMER OF ALL WARRANTIES. +'\" +'\" SCCS: @(#) SetOptions.3 1.6 98/01/10 15:33:01 +'\" +.so man.macros +.TH Tk_SetOptions 3 8.1 Tk "Tk Library Procedures" +.BS +.SH NAME +Tk_CreateOptionTable, Tk_DeleteOptionTable, Tk_InitOptions, Tk_SetOptions, Tk_FreeSavedOptions, Tk_RestoreSavedOptions, Tk_GetOptionValue, Tk_GetOptionInfo, Tk_FreeConfigOptions, Tk_Offset \- process configuration options +.SH SYNOPSIS +.nf +\fB#include <tk.h>\fR +.sp +Tk_OptionTable +\fBTk_CreateOptionTable(\fIinterp, templatePtr\fB)\fR +.sp +\fBTk_DeleteOptionTable(\fIoptionTable\fB)\fR +.sp +int +\fBTk_InitOptions(\fIinterp, recordPtr, optionTable, tkwin\fB)\fR +.sp +int +\fBTk_SetOptions(\fIinterp, recordPtr, optionTable, objc, objv, tkwin, savePtr, maskPtr\fB)\fR +.sp +\fBTk_FreeSavedOptions(\fIsavedPtr\fB)\fR +.sp +\fBTk_RestoreSavedOptions(\fIsavedPtr\fB)\fR +.sp +Tcl_Obj * +\fBTk_GetOptionValue(\fIinterp, recordPtr, optionTable, namePtr, tkwin\fB)\fR +.sp +Tcl_Obj * +\fBTk_GetOptionInfo(\fIinterp, recordPtr, optionTable, namePtr, tkwin\fB)\fR +.sp +\fBTk_FreeConfigOptions(\fIrecordPtr, optionTable, tkwin\fB)\fR +.sp +int +\fBTk_Offset(\fItype, field\fB)\fR +.SH ARGUMENTS +.AS Tk_SavedOptions "*CONST objv[]" in/out +.AP Tcl_Interp *interp in +A Tcl interpreter. Most procedures use this only for returning error +messages; if it is NULL then no error messages are returned. For +\fBTk_CreateOptionTable\fR the value cannot be NULL; it gives the +interpreter in which the option table will be used. +.AP Tk_OptionSpec *templatePtr in +Points to an array of static information that describes the configuration +options that are supported. Used to build a Tk_OptionTable. The information +pointed to by this argument must exist for the lifetime of the Tk_OptionTable. +.AP Tk_OptionTable optionTable in +Token for an option table. Must have been returned by a previous call +to \fBTk_CreateOptionTable\fR. +.AP char *recordPtr in/out +Points to structure in which values of configuration options are stored; +fields of this record are modified by procedures such as \fBTk_SetOptions\fR +and read by procedures such as \fBTk_GetOptionValue\fR. +.AP Tk_Window tkwin in +For options such as TK_OPTION_COLOR, this argument indicates +the window in which the option will be used. If \fIoptionTable\fR uses +no window-dependent options, then a NULL value may be supplied for +this argument. +.AP int objc in +Number of values in \fIobjv\fR. +.AP Tcl_Obj "*CONST objv[]" in +Command-line arguments for setting configuring options. +.AP Tk_SavedOptions *savePtr out +If not NULL, the structure pointed to by this argument is filled +in with the old values of any options that were modified and old +values are restored automatically if an error occurs in \fBTk_SetOptions\fR. +.AP int *maskPtr out +If not NULL, the word pointed to by \fImaskPtr\fR is filled in with the +bit-wise OR of the \fItypeMask\fR fields for the options that +were modified. +.AP Tk_SavedOptions *savedPtr in/out +Points to a structure previously filled in by \fBTk_SetOptions\fR with +old values of modified options. +.AP Tcl_Obj *namePtr in +The value of this object is the name of a particular option. If NULL +is passed to \fBTk_GetOptionInfo\fR then information is returned for +all options. Must not be NULL when \fBTk_GetOptionValue\fR is called. +.AP "type name" type in +The name of the type of a record. +.AP "field name" field in +The name of a field in records of type \fItype\fR. +.BE +.SH DESCRIPTION +.PP +These procedures handle most of the details of parsing configuration +options such as those for Tk widgets. Given a description of what +options are supported, these procedures handle all the details of +parsing options and storing their values into a C structure associated +with the widget or object. The procedures were designed primarily for +widgets in Tk, but they can also be used for other kinds of objects that +have configuration options. In the rest of this manual page ``widget'' will +be used to refer to the object whose options are being managed; in +practice the object may not actually be a widget. The term ``widget +record'' is used to refer to the C-level structure in +which information about a particular widget or object is stored. +.PP +Note: the easiest way to learn how to use these procedures is to +look at a working example. In Tk, the simplest example is the code +that implements the button family of widgets, which is an \fBtkButton.c\fR. +Other examples are in \fBtkSquare.c\fR and \fBtkMenu.c\fR. +.PP +In order to use these procedures, the code that implements the widget +must contain a static array of Tk_OptionSpec structures. This is a +template that describes the various options supported by that class of +widget; there is a separate template for each kind of widget. The +template contains information such as the name of each option, its type, +its default value, and where the value of the option is stored in the +widget record. See TEMPLATES below for more detail. +.PP +In order to process configuration options efficiently, the static +template must be augmented with additional information that is available +only at runtime. The procedure \fBTk_CreateOptionTable\fR creates this +dynamic information from the template and returns a Tk_OptionTable token +that describes both the static and dynamic information. All of the +other procedures, such as \fBTk_SetOptions\fR, take a Tk_OptionTable +token as argument. Typically, \fBTk_CreateOptionTable\fR is called the +first time that a widget of a particular class is created and the +resulting Tk_OptionTable is used in the future for all widgets of that +class. A Tk_OptionTable may be used only in a single interpreter, given +by the \fIinterp\fR argument to \fBTk_CreateOptionTable\fR. When an +option table is no longer needed \fBTk_DeleteOptionTable\fR should be +called to free all of its resources. All of the option tables +for a Tcl interpreter are freed automatically if the interpreter is deleted. +.PP +\fBTk_InitOptions\fR is invoked when a new widget is created to set +the default values for all of the widget's configuration options. +\fBTk_InitOptions\fR is passed a token for an option table (\fIoptionTable\fR) +and a pointer to a widget record (\fIrecordPtr\fR), which is the C +structure that holds information about this widget. \fBTk_InitOptions\fR +uses the information in the option table to +choose an appropriate default for each option, then it stores the default +value directly into the widget record, overwriting any information that +was already present in the widget record. \fBTk_InitOptions\fR normally +returns TCL_OK. If an error occurred while setting the default values +(e.g., because a default value was erroneous) then TCL_ERROR is returned +and an error message is left in \fIinterp\fR's result if \fIinterp\fR +isn't NULL. +.PP +\fBTk_SetOptions\fR is invoked to modify configuration options based +on information specified in a Tcl command. The command might be one that +creates a new widget, or a command that modifies options on an existing +widget. The \fIobjc\fR and \fIobjv\fR arguments describe the +values of the arguments from the Tcl command. \fIObjv\fR must contain +an even number of objects: the first object of each pair gives the name of +an option and the second object gives the new value for that option. +\fBTk_SetOptions\fR looks up each name in \fIoptionTable\fR, checks that +the new value of the option conforms to the type in \fIoptionTable\fR, +and stores the value of the option into the widget record given by +\fIrecordPtr\fR. \fBTk_SetOptions\fR normally returns TCL_OK. If +an error occurred (such as an unknown option name or an illegal option +value) then TCL_ERROR is returned and an error message is left in +\fIinterp\fR's result if \fIinterp\fR isn't NULL. +.PP +\fBTk_SetOptions\fR has two additional features. First, if the +\fImaskPtr\fR argument isn't NULL then it points to an integer +value that is filled in with information about the options that were +modified. For each option in the template passed to +\fBTk_CreateOptionTable\fR there is a \fItypeMask\fR field. The +bits of this field are defined by the code that implements the widget; +for example, each bit might correspond to a particular configuration option. +Alternatively, bits might be used functionally. For example, one bit might +be used for redisplay: all options that affect the widget's display, such +that changing the option requires the widget to be redisplayed, might have +that bit set. Another bit might indicate that the geometry of the widget +must be recomputed, and so on. \fBTk_SetOptions\fR OR's together the +\fItypeMask\fR fields from all the options that were modified and returns +this value at *\fImaskPtr\fR; the caller can then use this information +to optimize itself so that, for example, it doesn't redisplay the widget +if the modified options don't affect the widget's appearance. +.PP +The second additional feature of \fBTk_SetOptions\fR has to do with error +recovery. If an error occurs while processing configuration options, this +feature makes it possible to restore all the configuration options to their +previous values. Errors can occur either while processing options in +\fBTk_SetOptions\fR or later in the caller. In many cases the caller does +additional processing after \fBTk_SetOptions\fR returns; for example, it +might use an option value to set a trace on a variable and may detect +an error if the variable is an array instead of a scalar. Error recovery +is enabled by passing in a non-NULL value for the \fIsavePtr\fR argument +to \fBTk_SetOptions\fR; this should be a pointer to an uninitialized +Tk_SavedOptions structure on the caller's stack. \fBTk_SetOptions\fR +overwrites the structure pointed to by \fIsavePtr\fR with information +about the old values of any options modified by the procedure. +If \fBTk_SetOptions\fR returns successfully, the +caller uses the structure in one of two ways. If the caller completes +its processing of the new options without any errors, then it must pass +the structure to \fBTk_FreeSavedOptions\fR so that the old values can be +freed. If the caller detects an error in its processing of the new +options, then it should pass the structure to \fBTk_RestoreSavedOptions\fR, +which will copy the old values back into the widget record and free +the new values. +If \fBTk_SetOptions\fR detects an error then it automatically restores +any options that had already been modified and leaves *\fIsavePtr\fR in +an empty state: the caller need not call either \fBTk_FreeSavedOptions\fR or +\fBTk_RestoreSavedOptions\fR. +If the \fIsavePtr\fR argument to \fBTk_SetOptions\fR is NULL then +\fBTk_SetOptions\fR frees each old option value immediately when it sets a new +value for the option. In this case, if an error occurs in the third +option, the old values for the first two options cannot be restored. +.PP +\fBTk_GetOptionValue\fR returns the current value of a configuration option +for a particular widget. The \fInamePtr\fR argument contains the name of +an option; \fBTk_GetOptionValue\fR uses \fIoptionTable\fR +to lookup the option and extract its value from the widget record +pointed to by \fIrecordPtr\fR, then it returns an object containing +that value. If an error occurs (e.g., because \fInamePtr\fR contains an +unknown option name) then NULL is returned and an error message is left +in \fIinterp\fR's result unless \fIinterp\fR is NULL. +.PP +\fBTk_GetOptionInfo\fR returns information about configuration options in +a form suitable for \fBconfigure\fR widget commands. If the \fInamePtr\fR +argument is not NULL, it points to an object that gives the name of a +configuration option; \fBTk_GetOptionInfo\fR returns an object containing +a list with five elements, which are the name of the option, the name and +class used for the option in the option database, the default value for +the option, and the current value for the option. If the \fInamePtr\fR +argument is NULL, then \fBTk_GetOptionInfo\fR returns information about +all options in the form of a list of lists; each sublist describes one +option. Synonym options are handled differently depending on whether +\fInamePtr\fR is NULL: if \fInamePtr\fR is NULL then the sublist for +each synonym option has only two elements, which are the name of the +option and the name of the other option that it refers to; if \fInamePtr\fR +is non-NULL and names a synonym option then the object returned +is the five-element list +for the other option that the synonym refers to. If an error occurs +(e.g., because \fInamePtr\fR contains an unknown option name) then NULL +is returned and an error message is left in \fIinterp\fR's result unless +\fIinterp\fR is NULL. +.PP +\fBTk_FreeConfigOptions\fR must be invoked when a widget is deleted. +It frees all of the resources associated with any of the configuration +options defined in \fIrecordPtr\fR by \fIoptionTable\fR. +.PP +The \fBTk_Offset\fR macro is provided as a safe way of generating the +\fIobjOffset\fR and \fIinternalOffset\fR values for entries in +Tk_OptionSpec structures. It takes two arguments: the name of a type +of record, and the name of a field in that record. It returns the byte +offset of the named field in records of the given type. + +.SH "TEMPLATES" +.PP +The array of Tk_OptionSpec structures passed to \fBTk_CreateOptionTable\fR +via its \fItemplatePtr\fR argument describes the configuration options +supported by a particular class of widgets. Each structure specifies +one configuration option and has the following fields: +.CS +typedef struct { + Tk_OptionType \fItype\fR; + char *\fIoptionName\fR; + char *\fIdbName\fR; + char *\fIdbClass\fR; + char *\fIdefValue\fR; + int \fIobjOffset\fR; + int \fIinternalOffset\fR; + int \fIflags\fR; + ClientData \fIclientData\fR; + int \fItypeMask\fR; +} Tk_OptionSpec; +.CE +The \fItype\fR field indicates what kind of configuration option this is +(e.g. TK_OPTION_COLOR for a color value, or TK_OPTION_INT for +an integer value). \fIType\fR determines how the +value of the option is parsed (more on this below). +The \fIoptionName\fR field is a string such as \fB\-font\fR or \fB\-bg\fR; +it is the name used for the option in Tcl commands and passed to +procedures via the \fIobjc\fR or \fInamePtr\fR arguments. +The \fIdbName\fR and \fIdbClass\fR fields are used by \fBTk_InitOptions\fR +to look up a default value for this option in the option database; if +\fIdbName\fR is NULL then the option database is not used by +\fBTk_InitOptions\fR for this option. The \fIdefValue\fR field +specifies a default value for this configuration option if no +value is specified in the option database. The \fIobjOffset\fR and +\fIinternalOffset\fR fields indicate where to store the value of this +option in widget records (more on this below); values for the \fIobjOffset\fR +and \fIinternalOffset\fR fields should always be generated with the +\fBTk_Offset\fR macro. +The \fIflags\fR field contains additional information +to control the processing of this configuration option (see below +for details). +\fIClientData\fR provides additional type-specific data needed +by certain types. For instance, for TK_OPTION_COLOR types, +\fIclientData\fR is a string giving the default value to use on +monochrome displays. See the descriptions of the different types +below for details. +The last field, \fItypeMask\fR, is used by \fBTk_SetOptions\fR to +return information about which options were modified; see the description +of \fBTk_SetOptions\fR above for details. +.PP +When \fBTk_InitOptions\fR and \fBTk_SetOptions\fR store the value of an +option into the widget record, they can do it in either of two ways. +If the \fIobjOffset\fR field of the Tk_OptionSpec is greater than +or equal to zero, then the value of the option is stored as a +(Tcl_Obj *) at the location in the widget record given by \fIobjOffset\fR. +If the \fIinternalOffset\fR field of the Tk_OptionSpec is +greater than or equal to zero, then the value of the option is stored +in a type-specific internal form at the location in the widget record +given by \fIinternalOffset\fR. For example, if the option's type is +TK_OPTION_INT then the internal form is an integer. If the +\fIobjOffset\fR or \fIinternalOffset\fR field is negative then the +value is not stored in that form. At least one of the offsets must be +greater than or equal to zero. +.PP +The \fIflags\fR field consists of one or more bits ORed together. At +present only a single flag is supported: TK_OPTION_NULL_OK. If +this bit is set for an option then an empty string will be accepted as +the value for the option and the resulting internal form will be a +NULL pointer or \fBNone\fR, depending on the type of the option. +If the flag is not set then empty strings will result +in errors. +TK_OPTION_NULL_OK is typically used to allow a +feature to be turned off entirely, e.g. set a cursor value to +\fBNone\fR so that a window simply inherits its parent's cursor. +Not all option types support the TK_OPTION_NULL_OK +flag; for those that do, there is an explicit indication of that fact +in the descriptions below. +.PP +The \fItype\fR field of each Tk_OptionSpec structure determines +how to parse the value of that configuration option. The +legal value for \fItype\fR, and the corresponding actions, are +described below. If the type requires a \fItkwin\fR value to be +passed into procedures like \fBTk_SetOptions\fR, or if it uses +the \fIclientData\fR field of the Tk_OptionSpec, then it is indicated +explicitly; if not mentioned, the type requires neither \fItkwin\fR +nor \fIclientData\fR. +.TP +\fBTK_OPTION_ANCHOR\fR +The value must be a standard anchor position such as \fBne\fR or +\fBcenter\fR. The internal form is a Tk_Anchor value like the ones +returned by \fBTk_GetAnchorFromObj\fR. +.TP +\fBTK_OPTION_BITMAP\fR +The value must be a standard Tk bitmap name. The internal form is a +Pixmap token like the ones returned by \fBTk_AllocBitmapFromObj\fR. +This option type requires \fItkwin\fR to be supplied to procedures +such as \fBTk_SetOptions\fR, and it supports the TK_OPTION_NULL_OK flag. +.TP +\fBTK_OPTION_BOOLEAN\fR +The value must be a standard boolean value such as \fBtrue\fR or +\fBno\fR. The internal form is an integer with value 0 or 1. +.TP +\fBTK_OPTION_BORDER\fR +The value must be a standard color name such as \fBred\fR or \fB#ff8080\fR. +The internal form is a Tk_3DBorder token like the ones returned +by \fBTk_Alloc3DBorderFromObj\fR. +This option type requires \fItkwin\fR to be supplied to procedures +such as \fBTk_SetOptions\fR, and it supports the TK_OPTION_NULL_OK flag. +.TP +\fBTK_OPTION_COLOR\fR +The value must be a standard color name such as \fBred\fR or \fB#ff8080\fR. +The internal form is an (XColor *) token like the ones returned by +\fBTk_AllocColorFromObj\fR. +This option type requires \fItkwin\fR to be supplied to procedures +such as \fBTk_SetOptions\fR, and it supports the TK_OPTION_NULL_OK flag. +.TP +\fBTK_OPTION_CURSOR\fR +The value must be a standard cursor name such as \fBcross\fR or \fB@foo\fR. +The internal form is a Tk_Cursor token like the ones returned by +\fBTk_AllocCursorFromObj\fR. +This option type requires \fItkwin\fR to be supplied to procedures +such as \fBTk_SetOptions\fR, and when the option is set the cursor +for the window is changed by calling \fBXDefineCursor\fR. This +option type also supports the TK_OPTION_NULL_OK flag. +.TP +\fBTK_OPTION_DOUBLE\fR +The string value must be a floating-point number in +the format accepted by \fBstrtol\fR. The internal form is a C +\fBdouble\fR value. +.TP +\fBTK_OPTION_END\fR +Marks the end of the template. There must be a Tk_OptionSpec structure +with \fItype\fR TK_OPTION_END at the end of each template. If the +\fIclientData\fR field of this structure isn't NULL, then it points to +an additional array of Tk_OptionSpec's, which is itself terminated by +another TK_OPTION_END entry. Templates may be chained arbitrarily +deeply. This feature allows common options to be shared by several +widget classes. +.TP +\fBTK_OPTION_FONT\fR +The value must be a standard font name such as \fBTimes 16\fR. +The internal form is a Tk_Font handle like the ones returned by +\fBTk_AllocFontFromObj\fR. +This option type requires \fItkwin\fR to be supplied to procedures +such as \fBTk_SetOptions\fR, and it supports the TK_OPTION_NULL_OK flag. +.TP +\fBTK_OPTION_INT\fR +The string value must be an integer in the format accepted by +\fBstrtol\fR (e.g. \fB0\fR and \fB0x\fR prefixes may be used to +specify octal or hexadecimal numbers, respectively). The internal +form is a C \fBint\fR value. +.TP +\fBTK_OPTION_JUSTIFY\fR +The value must be a standard justification value such as \fBleft\fR. +The internal form is a Tk_Justify like the values returned by +\fBTk_GetJustifyFromObj\fR. +.TP +\fBTK_OPTION_PIXELS\fR +The value must specify a screen distance such as \fB2i\fR or \fB6.4\fR. +The internal form is an integer value giving a +distance in pixels, like the values returned by +\fBTk_GetPixelsFromObj\fR. Note: if the \fIobjOffset\fR field isn't +used then information about the original value of this option will be lost. +See \fBOBJOFFSET VS. INTERNALOFFSET\fR below for details. +.TP +\fBTK_OPTION_RELIEF\fR +The value must be standard relief such as \fBraised\fR. +The internal form is an integer relief value such as +TK_RELIEF_RAISED. +.TP +\fBTK_OPTION_STRING\fR +The value may be any string. The internal form is a (char *) pointer +that points to a dynamically allocated copy of the value. +This option type supports the TK_OPTION_NULL_OK flag. +.TP +\fBTK_OPTION_STRING_TABLE\fR +For this type, \fIclientData\fR is a pointer to an array of strings +suitable for passing to \fBTcl_GetIndexFromObj\fR. The value must +be one of the strings in the table, or a unique abbreviation of +one of the strings. The internal form is an integer giving the index +into the table of the matching string, like the return value +from \fBTcl_GetStringFromObj\fR. +.TP +\fBTK_OPTION_SYNONYM\fR +This type is used to provide alternative names for an option (for +example, \fB\-bg\fR is often used as a synonym for \fB\-background\fR). +The \fBclientData\fR field is a (char *) pointer that gives +the name of another option in the same table. Whenever the +synonym option is used, the information from the other option +will be used instead. +.TP +\fBTK_OPTION_WINDOW\fR +The value must be a window path name. The internal form is a +\fBTk_Window\fR token for the window. +This option type requires \fItkwin\fR to be supplied to procedures +such as \fBTk_SetOptions\fR (in order to identify the application), +and it supports the TK_OPTION_NULL_OK flag. + +.SH "STORAGE MANAGEMENT ISSUES" +.PP +If a field of a widget record has its offset stored in the \fIobjOffset\fR +or \fIinternalOffset\fR field of a Tk_OptionSpec structure then the +procedures described here will handle all of the storage allocation and +resource management issues associated with the field. When the value +of an option is changed, \fBTk_SetOptions\fR (or \fBTk_FreeSavedOptions\fR +will automatically free any resources associated with the old value, such as +Tk_Fonts for TK_OPTION_FONT options or dynamically allocated memory for +TK_OPTION_STRING options. For an option stored as an object using the +\fIobjOffset\fR field of a Tk_OptionSpec, the widget record shares the +object pointed to by the \fIobjv\fR value from the call to +\fBTk_SetOptions\fR. The reference count for this object is incremented +when a pointer to it is stored in the widget record and decremented when +the option is modified. When the widget is deleted +\fBTk_FreeConfigOptions\fR should be invoked; it will free the resources +associated with all options and decrement reference counts for any +objects. +.PP +However, the widget code is responsible for storing NULL or \fBNone\fR in +all pointer and token fields before invoking \fBTk_InitOptions\fR. +This is needed to allow proper cleanup in the rare case where +an error occurs in \fBTk_InitOptions\fR. + +.SH "OBJOFFSET VS. INTERNALOFFSET" +.PP +In most cases it is simplest to use the \fIinternalOffset\fR field of +a Tk_OptionSpec structure and not the \fIobjOffset\fR field. This +makes the internal form of the value immediately available to the +widget code so the value doesn't have to be extracted from an object +each time it is used. However, there are two cases where the +\fIobjOffset\fR field is useful. The first case is for +TK_OPTION_PIXELS options. In this case, the internal form is +an integer pixel value that is valid only for a particular screen. +If the value of the option is retrieved, it will be returned as a simple +number. For example, after the command \fB.b configure \-borderwidth 2m\fR, +the command \fB.b configure \-borderwidth\fR might return 7, which is the +integer pixel value corresponding to \fB2m\fR. Unfortunately, this loses +the original screen-independent value. Thus for TK_OPTION_PIXELS options +it is better to use the \fIobjOffset\fR field. In this case the original +value of the option is retained in the object and can be returned when +the option is retrieved. In most cases it is convenient to use the +\fIinternalOffset\fR field field as well, so that the integer value is +immediately available for use in the widget code (alternatively, +\fBTk_GetPixelsFromObj\fR can be used to extract the integer value from +the object whenever it is needed). Note: the problem of losing information +on retrievals exists only for TK_OPTION_PIXELS options. +.PP +The second reason to use the \fIobjOffset\fR field is in order to +implement new types of options not supported by these procedures. +To implement a new type of option, use TK_OPTION_STRING as +the type in the Tk_OptionSpec structure and set the \fIobjOffset\fR field +but not the \fIinternalOffset\fR field. Then, after calling +\fBTk_SetOptions\fR, convert the object to internal form yourself. + +.SH KEYWORDS +anchor, bitmap, boolean, border, color, configuration option, +cursor, double, font, integer, justify, +pixels, relief, screen distance, synonym |