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XQueryColor(3)			 XLIB FUNCTIONS 		  XQueryColor(3)

NAME
     XQueryColor, XQueryColors, XLookupColor, XParseColor - obtain color values

SYNTAX
     int XQueryColor(Display *display, Colormap colormap, XColor *def_in_out);

     int XQueryColors(Display *display, Colormap colormap, XColor defs_in_out[],
	    int ncolors);

     Status  XLookupColor(Display  *display,  Colormap	colormap,  _Xconst  char
	    *color_name, XColor *exact_def_return, XColor *screen_def_return);

     Status XParseColor(Display *display, Colormap colormap, _Xconst char *spec,
	    XColor *exact_def_return);

ARGUMENTS
     colormap  Specifies the colormap.

     color_nameSpecifies the color name string (for example,  red)  whose  color
	       definition structure you want returned.

     def_in_outSpecifies  and  returns the RGB values for the pixel specified in
	       the structure.

     defs_in_out
	       Specifies and returns an array of color definition structures for
	       the pixel specified in the structure.

     display   Specifies the connection to the X server.

     exact_def_return
	       Returns the exact RGB values.

     ncolors   Specifies the number of XColor structures in the color definition
	       array.

     screen_def_return
	       Returns the closest RGB values provided by the hardware.

     spec      Specifies the color name string; case is ignored.

     exact_def_return
	       Returns the exact color value for later use and sets  the  DoRed,
	       DoGreen, and DoBlue flags.

DESCRIPTION
     The XQueryColor function returns the current RGB value for the pixel in the
     XColor  structure	and  sets  the	DoRed,	DoGreen,  and DoBlue flags.  The
     XQueryColors function returns the RGB value for each pixel in  each  XColor
     structure and sets the DoRed, DoGreen, and DoBlue flags in each structure.

     XQueryColor and XQueryColors can generate BadColor and BadValue errors.

     The  XLookupColor function looks up the string name of a color with respect
     to the screen associated with the specified colormap.  It returns both  the
     exact  color  values and the closest values provided by the screen with re-
     spect to the visual type of the specified colormap.  If the color	name  is
     not  in the Host Portable Character Encoding, the result is implementation-
     dependent.  Use of uppercase or lowercase does  not  matter.   XLookupColor
     returns nonzero if the name is resolved; otherwise, it returns zero.

     The  XParseColor  function looks up the string name of a color with respect
     to the screen associated with the specified colormap.  It returns the exact
     color value.  If the color name is not in the Host Portable  Character  En-
     coding, the result is implementation-dependent.  Use of uppercase or lower-
     case does not matter.  XParseColor returns nonzero if the name is resolved;
     otherwise, it returns zero.

     XLookupColor and XParseColor can generate BadColor error.

COLOR NAMES
     An RGB Device specification is identified by the prefix "rgb:" and conforms
     to the following syntax:

     rgb:<red>/<green>/<blue>

	 <red>, <green>, <blue> := h | hh | hhh | hhhh
	 h := single hexadecimal digits (case insignificant)

     Note  that h indicates the value scaled in 4 bits, hh the value scaled in 8
     bits, hhh the value scaled in 12 bits, and hhhh  the  value  scaled  in  16
     bits, respectively.

     For  backward  compatibility,  an older syntax for RGB Device is supported,
     but its continued use is not encouraged.  The syntax is  an  initial  sharp
     sign character followed by a numeric specification, in one of the following
     formats:

     #RGB	     (4 bits each)
     #RRGGBB	     (8 bits each)
     #RRRGGGBBB      (12 bits each)
     #RRRRGGGGBBBB   (16 bits each)

     The  R,  G,  and B represent single hexadecimal digits.  When fewer than 16
     bits each are specified, they represent the most significant  bits  of  the
     value (unlike the "rgb:" syntax, in which values are scaled).  For example,
     the string "#3a7" is the same as "#3000a0007000".

     An RGB intensity specification is identified by the prefix "rgbi:" and con-
     forms to the following syntax:

     rgbi:<red>/<green>/<blue>

     Note  that  red,  green, and blue are floating-point values between 0.0 and
     1.0, inclusive.  The input format for these values is an optional	sign,  a
     string  of numbers possibly containing a decimal point, and an optional ex-
     ponent field containing an E or e followed by  a  possibly  signed  integer
     string.

     The  standard  device-independent	string specifications have the following
     syntax:

     CIEXYZ:<X>/<Y>/<Z>
     CIEuvY:<u>/<v>/<Y>
     CIExyY:<x>/<y>/<Y>
     CIELab:<L>/<a>/<b>
     CIELuv:<L>/<u>/<v>
     TekHVC:<H>/<V>/<C>

     All of the values (C, H, V, X, Y, Z, a, b, u, v, y, x)  are  floating-point
     values.   The  syntax for these values is an optional plus or minus sign, a
     string of digits possibly containing a decimal point, and an optional expo-
     nent field consisting of an "E" or "e" followed by an optional plus or  mi-
     nus followed by a string of digits.

DIAGNOSTICS
     BadColor  A value for a Colormap argument does not name a defined Colormap.

     BadValue  Some  numeric value falls outside the range of values accepted by
	       the request.  Unless a specific range is specified for  an  argu-
	       ment,  the full range defined by the argument's type is accepted.
	       Any argument defined as a set of alternatives can  generate  this
	       error.

SEE ALSO
     XAllocColor(3), XCreateColormap(3), XStoreColors(3)
     Xlib - C Language X Interface

X Version 11			  libX11 1.8.13 		  XQueryColor(3)

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