xlookupcolor(3) [hpux man page]
XLookupColor() XLookupColor() Name XLookupColor - get database RGB values and closest hardware-supported RGB values from color name. Synopsis Status XLookupColor(display, colormap, colorname, exact_def_return, screen_def_return) Display *display; Colormap colormap; char *colorname; XColor *exact_def_return, *screen_def_return; Arguments display Specifies a connection to an X server; returned from XOpenDisplay(). colormap Specifies the colormap. colorname Specifies a color name string (for example "red"). Uppercase or lowercase does not matter. If the color name is not in the Host Portable Character Encoding, the result is implementation-dependent. exact_def_return Returns the exact RGB values for the specified color name from the /usr/lib/X11/rgb database. screen_def_return Returns the closest RGB values possible on the hardware. Returns Zero on failure, non-zero on success. Description XLookupColor() looks up RGB values for a color given the colorname string. It returns both the exact color values and the closest values possible on tthe screen specified by colormap. XLookupColor() returns non-zero if colorname exists in the RGB database or zero if it does not exist. To determine the exact RGB values, XLookupColor() uses a database on the X server. On UNIX, this database is /usr/lib/X11/rgb. To read the colors provided by the database on a UNIX-based system, see /usr/lib/X11/rgb.txt. The location, name, and contents of this file are server-dependent. For more information see Volume One, Chapter 7, Color, and Appendix D, The Server-side Color Database, in this volume. Errors BadName Color name not in database. BadColor Invalid colormap. Structures typedef struct { unsigned long pixel; unsigned short red, green, blue; char flags; /* DoRed, DoGreen, DoBlue */ char pad; } XColor; See Also XBlackPixel(), XWhitePixel(), XAllocColor(), XAllocColorCells(), XAllocColorPlanes(), XAllocNamedColor(), XFreeColors(), XParseColor(), XQueryColor(), XQueryColors(), XStoreColor(), XStoreColors(), XStoreNamedColor(). Xlib - Color Cells XLookupColor()
Check Out this Related Man Page
XParseColor() XParseColor() Name XParseColor - look up RGB values from ASCII color name or translate hexadecimal value. Synopsis Status XParseColor(display, colormap, spec, exact_def_return) Display *display; Colormap colormap; char *spec; XColor *exact_def_return; Arguments display Specifies a connection to an X server; returned from XOpenDisplay(). colormap Specifies a colormap associated with the screen on which to look up the color. This argument is required, but is meaningful only with Xcms color specifications. spec Specifies the color string (see the "Description" section). Uppercase or lowercase does not matter. If the color name is not in the Host Portable Character Encoding, the result is implementation-dependent. exact_def_return Returns the RGB values corresponding to the specified color name or hexadecimal specification, and sets its DoRed, DoGreen, and DoBlue flags. Returns Zero on failure, non-zero on success. Description XParseColor() looks up the string name of a color with respect to the screen associated with the specified colormap. It returns the exact color value. It or hexadecimal values specified, or translating the hexadecimal code into separate RGB values. XParseColor() takes a string specification of a color, typically from a user-specified command line or resource value, and returns the cor- responding red, green, and blue values, suitable for a subsequent call to XAllocColor or XStoreColor(). spec can be given in several forms, and may be looked up in different ways depending on the form. o Color name, such as "blue". This form is looked up in the server's RGB database, a sample of which is listed in Appendix D, The Server- side Color Database. o Xcms color name, such as TekHVC:0.0/100.0/0.0. This form is looked up in the client-side database for the screen associated with the specified colormap. This form is supported starting in Release 5. For more information on this form of color specification, see the Programmer's Supplement for Release 5, or the Third Edition of Volume One. o Hexadecimal specification such as #3a7. This form consists of an initial sharp sign character followed by one of the following formats: #RGB (one character per color) #RRGGBB (two characters per color) #RRRGGGBBB (three characters per color) #RRRRGGGGBBBB (four characters per color) where R, G, and B represent single hexadecimal digits (uppercase or lowercase). The hexadecimal strings must be NULL-terminated so that XParseColor() knows when it has reached the end. When fewer than 16 bits each are specified, they represent the most significant bits of the value. For example, #3a7 is the same as #3000a0007000. The hexadecimal style is discouraged in Release 5 and later. Status is zero on failure, non-zero on success. This routine will fail if the initial character is a sharp sign but the string otherwise fails to fit one of the above formats, or if the initial character is not a sharp sign and the named color does not exist in the server's database. For more information, see Volume One, Chapter 7, Color and in the Third Edition, the chapter on Device-Independent Color. Structures typedef struct { unsigned long pixel; unsigned short red, green, blue; char flags; /* DoRed, DoGreen, DoBlue */ char pad; } XColor; Errors BadColor Invalid colormap. See Also XBlackPixel(), XWhitePixel(), XAllocColor(), XcmsAllocColor(), XAllocColorCells(), XAllocColorPlanes(), XAllocNamedColor(), XcmsAllocNamed- Color(), XFreeColors(), XLookupColor(), XQueryColor(), XQueryColors(), XStoreColor(), XcmsStoreColor(), XStoreColors(), XcmsStoreColors(), XStoreNamedColor(). Xlib - Color Cells XParseColor()