option(n) Tk Built-In Commands option(n)
option - Add/retrieve window options to/from the option database
option add pattern value ?priority?
option get window name class
option readfile fileName ?priority?
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 sepa-
rated by asterisks or dots, in the usual X format. Value contains a text string to asso-
ciate 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 pri-
ority 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:
Level 20. Used for default values hard-coded into widgets.
Level 40. Used for options specified in application-specific startup files.
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
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.
database, option, priority, retrieve