font(n) 						       Tk Built-In Commands							   font(n)

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NAME

       font - Create and inspect fonts.

SYNOPSIS

       font option ?arg arg ...?
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DESCRIPTION

       The font command provides several facilities for dealing with fonts, such as defining named fonts and inspecting the actual attributes of a
       font.  The command has several different forms, determined by the first argument.  The following forms are currently supported:

       font actual font ?-displayof window? ?option?
	      Returns information about the the actual attributes that are obtained when font is used on window's display; the	actual	attributes
	      obtained	may  differ from the attributes requested due to platform-dependant limitations, such as the availability of font families
	      and pointsizes.  font is a font description; see FONT DESCRIPTIONS below.  If the window argument is omitted,  it  defaults  to  the
	      main  window.   If option is specified, returns the value of that attribute; if it is omitted, the return value is a list of all the
	      attributes and their values.  See FONT OPTIONS below for a list of the possible attributes.

       font configure fontname ?option? ?value option value ...?
	      Query or modify the desired attributes for the named font called fontname.  If no option is specified, returns a list describing all
	      the  options  and  their values for fontname.  If a single option is specified with no value, then returns the current value of that
	      attribute.  If one or more option-value pairs are specified, then the command modifies the given named font to have the  given  val-
	      ues;  in	this  case, all widgets using that font will redisplay themselves using the new attributes for the font.  See FONT OPTIONS
	      below for a list of the possible attributes.

       font create ?fontname? ?option value ...?
	      Creates a new named font and returns its name.  fontname specifies the name for the font; if it is omitted, then Tk generates a  new
	      name  of the form fontx, where x is an integer.  There may be any number of option-value pairs, which provide the desired attributes
	      for the new named font.  See FONT OPTIONS below for a list of the possible attributes.

       font delete fontname ?fontname ...?
	      Delete the specified named fonts.  If there are widgets using the named font, the named font won't actually be deleted until all the
	      instances  are released.	Those widgets will continue to display using the last known values for the named font.	If a deleted named
	      font is subsequently recreated with another call to font create, the widgets will use the new named font	and  redisplay	themselves
	      using the new attributes of that font.

       font families ?-displayof window?
	      The  return  value is a list of the case-insensitive names of all font families that exist on window's display.  If the window argu-
	      ment is omitted, it defaults to the main window.

       font measure font ?-displayof window? text
	      Measures the amount of space the string text would use in the given font when displayed in window.  font is a font description;  see
	      FONT DESCRIPTIONS below.	If the window argument is omitted, it defaults to the main window.  The return value is the total width in
	      pixels of text, not including the extra pixels used by highly exagerrated characters such as cursive ``f''.  If the string  contains
	      newlines or tabs, those characters are not expanded or treated specially when measuring the string.

       font metrics font ?-displayof window? ?option?
	      Returns  information  about  the	metrics  (the  font-specific  data), for font when it is used on window's display.  font is a font
	      description; see FONT DESCRIPTIONS below.  If the window argument is omitted, it defaults to the main window.  If option	is  speci-
	      fied,  returns the value of that metric; if it is omitted, the return value is a list of all the metrics and their values.  See FONT
	      METRICS below for a list of the possible metrics.

       font names
	      The return value is a list of all the named fonts that are currently defined.

FONT DESCRIPTION

       The following formats are accepted as a font description anywhere font is specified as an argument above; these same forms are also permit-
       ted when specifying the -font option for widgets.

       [1] fontname
	      The  name  of a named font, created using the font create command.  When a widget uses a named font, it is guaranteed that this will
	      never cause an error, as long as the named font exists, no matter what potentially invalid or  meaningless  set  of  attributes  the
	      named  font has.	If the named font cannot be displayed with exactly the specified attributes, some other close font will be substi-
	      tuted automatically.

       [2] systemfont
	      The platform-specific name of a font, interpreted by the graphics server.  This also includes, under X, an XLFD (see [4]) for  which
	      a  single  ``*'' character was used to elide more than one field in the middle of the name.  See PLATFORM-SPECIFIC issues for a list
	      of the system fonts.

       [3] family ?size? ?style? ?style ...?													   |
	      A properly formed list whose first element is the desired font family and whose optional second element is the  desired  size.   The |
	      interpretation  of  the  size  attribute	follows the same rules described for -size in FONT OPTIONS below.  Any additional optional |
	      arguments following the size are font styles.  Possible values for the style arguments are as follows:				   |
	      normal	  bold	      roman	 italic underline   overstrike									   |

       [4] X-font names (XLFD)															   |
	      A Unix-centric font name	of  the  form  -foundry-family-weight-slant-setwidth-addstyle-pixel-point-resx-resy-spacing-width-charset- |
	      encoding.   The  ``*'' character may be used to skip individual fields that the user does not care about.  There must be exactly one |
	      ``*'' for each field skipped, except that a ``*'' at the end of the XLFD skips any remaining fields; the shortest valid XLFD is sim- |
	      ply  ``*'',  signifying  all fields as defaults.	Any fields that were skipped are given default values.	For compatibility, an XLFD |
	      always chooses a font of the specified pixel size (not point size); although this interpretation is not strictly correct, all exist- |
	      ing  applications  using	XLFDs assumed that one ``point'' was in fact one pixel and would display incorrectly (generally larger) if |
	      the correct size font were actually used.

       [5] option value ?option value ...?
	      A properly formed list of option-value pairs that specify the desired attributes of the font, in the same format used when  defining
	      a named font; see FONT OPTIONS below.

       When  font  description	font is used, the system attempts to parse the description according to each of the above five rules, in the order
       specified.  Cases [1] and [2] must match the name of an existing named font or of a system font.  Cases [3], [4], and [5] are  accepted	on
       all  platforms  and  the  closest available font will be used.  In some situations it may not be possible to find any close font (e.g., the
       font family was a garbage value); in that case, some system-dependant default font is chosen.  If the font description does not	match  any
       of the above patterns, an error is generated.

FONT METRICS

       The following options are used by the font metrics command to query font-specific data determined when the font was created.  These proper-
       ties are for the whole font itself and not for individual characters drawn in that font.  In the following definitions, the ``baseline'' of
       a font is the horizontal line where the bottom of most letters line up; certain letters, such as lower-case ``g'' stick below the baseline.

       -ascent
	      The  amount  in  pixels  that  the  tallest letter sticks up above the baseline of the font, plus any extra blank space added by the
	      designer of the font.

       -descent
	      The largest amount in pixels that any letter sticks down below the baseline of the font, plus any extra blank  space  added  by  the
	      designer of the font.

       -linespace
	      Returns  how far apart vertically in pixels two lines of text using the same font should be placed so that none of the characters in
	      one line overlap any of the characters in the other line.  This is generally the sum of the ascent above the baseline line plus  the
	      descent below the baseline.

       -fixed
	      Returns  a  boolean  flag  that is ``1'' if this is a fixed-width font, where each normal character is the the same width as all the
	      other characters, or is ``0'' if this is a proportionally-spaced font, where  individual	characters  have  different  widths.   The
	      widths of control characters, tab characters, and other non-printing characters are not included when calculating this value.

FONT OPTIONS

       The following options are supported on all platforms, and are used when constructing a named font or when specifying a font using style [5]
       as above:

       -family name
	      The case-insensitive font family name.  Tk guarantees to support the font families named Courier (a monospaced ``typewriter'' font),
	      Times  (a serifed ``newspaper'' font), and Helvetica (a sans-serif ``European'' font).  The most closely matching native font family
	      will automatically be substituted when one of the above font families is used.  The name may also be the name of a native, platform-
	      specific font family; in that case it will work as desired on one platform but may not display correctly on other platforms.  If the
	      family is unspecified or unrecognized, a platform-specific default font will be chosen.						   |

       -size size																   |
	      The desired size of the font.  If the size argument is a positive number, it is interpreted as a size in points.	If size is a nega- |
	      tive  number,  its absolute value is interpreted as a size in pixels.  If a font cannot be displayed at the specified size, a nearby |
	      size will be chosen.  If size is unspecified or zero, a platform-dependent default size will be chosen.				   |

	      Sizes should normally be specified in points so the application will remain the same ruler size on the screen,  even  when  changing |
	      screen resolutions or moving scripts across platforms.  However, specifying pixels is useful in certain circumstances such as when a |
	      piece of text must line up with respect to a fixed-size bitmap.  The mapping between points and pixels is set when  the  application |
	      starts, based on properties of the installed monitor, but it can be overridden by calling the tk scaling command. 		   |

       -weight weight
	      The  nominal  thickness of the characters in the font.  The value normal specifies a normal weight font, while bold specifies a bold
	      font.  The closest available weight to the one specified will be chosen.	The default weight is normal.

       -slant slant
	      The amount the characters in the font are slanted away from the vertical.  Valid values for slant are roman  and	italic.   A  roman
	      font  is	the  normal, upright appearance of a font, while an italic font is one that is tilted some number of degrees from upright.
	      The closest available slant to the one specified will be chosen.	The default slant is roman.

       -underline boolean
	      The value is a boolean flag that specifies whether characters in this font should be underlined.	The default value for underline is
	      false.

       -overstrike boolean
	      The  value is a boolean flag that specifies whether a horizontal line should be drawn through the middle of characters in this font.
	      The default value for overstrike is false.

PLATFORM-SPECIFIC ISSUES
       The following named system fonts are supported:

	      X Windows:
		     All valid X font names, including those listed by xlsfonts(1), are available.

	      MS Windows:
		     system	 ansi	     device systemfixed ansifixed   oemfixed

	      Macintosh:
		     system	 application

SEE ALSO

       options

KEYWORDS

       font

Tk									8.0								   font(n)