1option(n)                    Tk Built-In Commands                    option(n)
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NAME

8       option - Add/retrieve window options to/from the option database
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SYNOPSIS

11       option add pattern value ?priority?
12       option clear
13       option get window name class
14       option readfile fileName ?priority?
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DESCRIPTION

18       The  option command allows you to add entries to the Tk option database
19       or to retrieve options from the database.  The add form of the  command
20       adds  a  new option to the database.  Pattern contains the option being
21       specified, and consists of names and/or classes separated by  asterisks
22       or  dots, in the usual X format (see PATTERN FORMAT).  Value contains a
23       text string to associate with pattern;  this is the value that will  be
24       returned  in  calls to Tk_GetOption or by invocations of the option get
25       command.  If priority is specified, it indicates the priority level for
26       this  option (see below for legal values);  it defaults to interactive.
27       This command always returns an empty string.
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29       The option clear command clears the option database.   Default  options
30       (from  the  RESOURCE_MANAGER  property  or the .Xdefaults file) will be
31       reloaded automatically the next time an option is added to the database
32       or removed from it.  This command always returns an empty string.
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34       The  option  get  command returns the value of the option specified for
35       window under name and class.  If several entries in the option database
36       match  window,  name, and class, then the command returns whichever was
37       created with highest priority level.  If  there  are  several  matching
38       entries at the same priority level, then it returns whichever entry was
39       most recently entered into the option database.  If there are no match‐
40       ing entries, then the empty string is returned.
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42       The  readfile form of the command reads fileName, which should have the
43       standard format for an X resource database such as .Xdefaults, and adds
44       all the options specified in that file to the option database.  If pri‐
45       ority is specified, it indicates the priority level at which  to  enter
46       the options;  priority defaults to interactive.
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48       The  file  is  read  through  a  channel  which is in "utf-8" encoding,
49       invalid byte sequences are automatically converted to valid ones.  This
50       means  that  encodings  like ISO 8859-1 or cp1252 with high probability
51       will work as well, but this  cannot  be  guaranteed.   This  cannot  be
52       changed, setting the [encoding system] has no effect.
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54       The  priority  arguments  to  the option command are normally specified
55       symbolically using one of the following values:
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57       widgetDefault
58              Level 20.  Used for default values hard-coded into widgets.
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60       startupFile
61              Level 40.  Used for options  specified  in  application-specific
62              startup files.
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64       userDefault
65              Level  60.  Used for options specified in user-specific defaults
66              files, such as .Xdefaults, resource databases loaded into the  X
67              server, or user-specific startup files.
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69       interactive
70              Level  80.   Used  for options specified interactively after the
71              application starts running.  If priority is  not  specified,  it
72              defaults to this level.
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74       Any  of the above keywords may be abbreviated.  In addition, priorities
75       may be specified numerically using integers between 0 and  100,  inclu‐
76       sive.   The numeric form is probably a bad idea except for new priority
77       levels other than the ones given above.
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PATTERN FORMAT

80       Patterns consist of a sequence of words separated  by  either  periods,
81       “.”, or asterisks “*”.  The overall pattern may also be optionally pre‐
82       ceded by an asterisk.
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84       Each word in the pattern conventionally starts with  either  an  upper-
85       case  letter  (in which case it denotes the class of either a widget or
86       an option) or any other character, when it denotes the name of a widget
87       or  option.  The  last word in the pattern always indicates the option;
88       the preceding ones constrain which widgets that option will  be  looked
89       for in.
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91       When  two  words are separated by a period, the latter widget must be a
92       direct child of the former (or the option must apply to only the  indi‐
93       cated widgets).  When two words are separated by an asterisk, any depth
94       of widgets may lie between the  former  and  latter  widgets  (and  the
95       option applies to all widgets that are children of the former widget).
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97       If  the  overall  pattern  is preceded by an asterisk, then the overall
98       pattern applies anywhere it can throughout the whole widget  hierarchy.
99       Otherwise the first word of the pattern is matched against the name and
100       class of the “.toplevel, which are usually set by options to wish.
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EXAMPLES

103       Instruct every button in the application to have red text on it  unless
104       explicitly  overridden,  by setting the foreground for the Button class
105       (note that on some platforms the option is ignored):
106              option add *Button.foreground red startupFile
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108       Allow users to control what happens in an entry widget when the  Return
109       key  is pressed by specifying a script in the option database and add a
110       default option for that which rings the bell:
111              entry .e
112              bind .e <Return> [option get .e returnCommand Command]
113              option add *.e.returnCommand bell widgetDefault
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SEE ALSO

116       options(n), wish(1)
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KEYWORDS

119       database, option, priority, retrieve
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123Tk                                                                   option(n)
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