getfontstr(3Tk)

NAME
     Tk_GetFontStruct, Tk_NameOfFontStruct, Tk_FreeFontStruct - maintain
     database of fonts

SYNOPSIS
     #include <tk.h>

     XFontStruct *
     Tk_GetFontStruct(interp, tkwin, nameId)

     char *
     Tk_NameOfFontStruct(fontStructPtr)

     Tk_FreeFontStruct(fontStructPtr)

ARGUMENTS
     Tcl_Interp    *interp          (in)      Interpreter to use for error
                                              reporting.

     Tk_Window     tkwin            (in)      Token for window in which font
                                              will be used.

     Tk_Uid        nameId           (in)      Name of desired font.

     XFontStruct   *fontStructPtr   (in)      Font structure to return name
                                              for or delete.


DESCRIPTION
     Tk_GetFont loads the font indicated by nameId and returns a pointer to
     information about the font.  The pointer returned by Tk_GetFont will
     remain valid until Tk_FreeFont is called to release it.  NameId can be
     either a font name or pattern;  any value that could be passed to
     XLoadQueryFont may be passed to Tk_GetFont.  If Tk_GetFont is
     unsuccessful (because, for example, there is no font corresponding to
     nameId) then it returns NULL and stores an error message in interp-
     >result.

     Tk_GetFont maintains a database of all fonts it has allocated.  If the
     same nameId is requested multiple times (e.g. by different windows or for
     different purposes), then additional calls for the same nameId will be
     handled very quickly, without involving the X server.  For this reason,
     it is generally better to use Tk_GetFont in place of X library procedures
     like XLoadQueryFont.

     The procedure Tk_NameOfFontStruct is roughly the inverse of
     Tk_GetFontStruct.  If its fontStructPtr argument was created by
     Tk_GetFontStruct, then the return value is the nameId argument that was
     passed to Tk_GetFontStruct to create the font.  If fontStructPtr was not
     created by a call to Tk_GetFontStruct, then the return value is a
     hexadecimal string giving the X identifier for the associated font.
     Note:  the string returned by Tk_NameOfFontStruct is only guaranteed to
     persist until the next call to Tk_NameOfFontStruct.

     When a font returned by Tk_GetFont is no longer needed, Tk_FreeFont
     should be called to release it.  There should be exactly one call to
     Tk_FreeFont for each call to Tk_GetFont.  When a font is no longer in use
     anywhere (i.e. it has been freed as many times as it has been gotten)
     Tk_FreeFont will release it to the X server and delete it from the
     database.


KEYWORDS
     font