option(3Tk)

NAME
     option - Add/retrieve window options to/from the option database

SYNOPSIS
     option add pattern value ?priority?

     option clear

     option get window name class

     option readfile fileName ?priority?


DESCRIPTION
     The option command allows you to add entries to the Tk option database or
     to retrieve options from the database.  The add form of the command adds
     a new option to the database.  Pattern contains the option being
     specified, and consists of names and/or classes separated by asterisks or
     dots, in the usual X format.  Value contains a text string to associate
     with pattern;  this is the value that will be returned in calls to
     Tk_GetOption or by invocations of the option get command.  If priority is
     specified, it indicates the priority level for this option (see below for
     legal values);  it defaults to interactive.  This command always returns
     an empty string.

     The option clear command clears the option database.  Default options
     (from the RESOURCE_MANAGER property or the .Xdefaults file) will be
     reloaded automatically the next time an option is added to the database
     or removed from it.  This command always returns an empty string.

     The option get command returns the value of the option specified for
     window under name and class.  If several entries in the option database
     match window, name, and class, then the command returns whichever was
     created with highest priority level.  If there are several matching
     entries at the same priority level, then it returns whichever entry was
     most recently entered into the option database.  If there are no matching
     entries, then the empty string is returned.

     The readfile form of the command reads fileName, which should have the
     standard format for an X resource database such as .Xdefaults, and adds
     all the options specified in that file to the option database.  If
     priority is specified, it indicates the priority level at which to enter
     the options;  priority defaults to interactive.

     The priority arguments to the option command are normally specified
     symbolically using one of the following values:

     widgetDefault
          Level 20.  Used for default values hard-coded into widgets.
     startupFile
          Level 40.  Used for options specified in application-specific
          startup files.

     userDefault
          Level 60.  Used for options specified in user-specific defaults
          files, such as .Xdefaults, resource databases loaded into the X
          server, or user-specific startup files.

     interactive
          Level 80.  Used for options specified interactively after the
          application starts running.  If priority isn't specified, it
          defaults to this level.

     Any of the above keywords may be abbreviated.  In addition, priorities
     may be specified numerically using integers between 0 and 100, inclusive.
     The numeric form is probably a bad idea except for new priority levels
     other than the ones given above.


KEYWORDS
     database, option, priority, retrieve