XCreateWindow, XCreateSimpleWindow, XSetWindowAttributes - create windows and window attributes structure
Window XCreateWindow(Display *display, Window parent, int x, int y, unsigned int width, unsigned int height, unsigned int border_width, int depth, unsigned int class, Visual *visual, unsigned long valuemask, XSetWindowAttributes *attributes); Window XCreateSimpleWindow(Display *display, Window parent, int x, int y, unsigned int width, unsigned int height, unsigned int border_width, unsigned long border, unsigned long background);
attributes Specifies the structure from which the values (as specified by the value mask) are to be taken. The value mask should have the appropriate bits set to indicate which attributes have been set in the structure. background Specifies the background pixel value of the window. border Specifies the border pixel value of the window. border_width Specifies the width of the created window's border in pixels. class Specifies the created window's class. You can pass InputOutput, InputOnly, or CopyFromParent. A class of CopyFromParent means the class is taken from the parent. depth Specifies the window's depth. A depth of CopyFromParent means the depth is taken from the parent. display Specifies the connection to the X server. parent Specifies the parent window. valuemask Specifies which window attributes are defined in the attributes argument. This mask is the bitwise inclusive OR of the valid attribute mask bits. If valuemask is zero, the attributes are ignored and are not referenced. visual Specifies the visual type. A visual of CopyFromParent means the visual type is taken from the parent. width height Specify the width and height, which are the created window's inside dimensions and do not include the created window's borders. x y Specify the x and y coordinates, which are the top-left outside corner of the window's borders and are relative to the inside of the parent window's borders.
The XCreateWindow function creates an unmapped subwindow for a specified parent window, returns the window ID of the created window, and causes the X server to generate a CreateNotify event. The created window is placed on top in the stacking order with respect to siblings. The coordinate system has the X axis horizontal and the Y axis vertical with the origin [0, 0] at the upper-left corner. Coordinates are integral, in terms of pixels, and coincide with pixel centers. Each window and pixmap has its own coordinate system. For a window, the origin is inside the border at the inside, upper-left corner. The border_width for an InputOnly window must be zero, or a BadMatch error results. For class InputOutput, the visual type and depth must be a combination supported for the screen, or a BadMatch error results. The depth need not be the same as the parent, but the parent must not be a window of class InputOnly, or a BadMatch error results. For an InputOnly window, the depth must be zero, and the visual must be one supported by the screen. If either condition is not met, a BadMatch error results. The parent window, however, may have any depth and class. If you specify any invalid window attribute for a window, a BadMatch error results. The created window is not yet displayed (mapped) on the user's display. To display the window, call XMapWindow. The new window initially uses the same cursor as its parent. A new cursor can be defined for the new window by calling XDefineCursor. The window will not be visible on the screen unless it and all of its ancestors are mapped and it is not obscured by any of its ancestors. XCreateWindow can generate BadAlloc BadColor, BadCursor, BadMatch, BadPixmap, BadValue, and BadWindow errors. The XCreateSimpleWindow function creates an unmapped InputOutput subwindow for a specified parent window, returns the window ID of the created window, and causes the X server to generate a CreateNotify event. The created window is placed on top in the stacking order with respect to siblings. Any part of the window that extends outside its parent window is clipped. The border_width for an InputOnly window must be zero, or a BadMatch error results. XCreateSimpleWindow inherits its depth, class, and visual from its parent. All other window attributes, except background and border, have their default values. XCreateSimpleWindow can generate BadAlloc, BadMatch, BadValue, and BadWindow errors.
The XSetWindowAttributes structure contains: /* Window attribute value mask bits */ #define CWBackPixmap (1L<<0) #define CWBackPixel (1L<<1) #define CWBorderPixmap (1L<<2) #define CWBorderPixel (1L<<3) #define CWBitGravity (1L<<4) #define CWWinGravity (1L<<5) #define CWBackingStore (1L<<6) #define CWBackingPlanes (1L<<7) #define CWBackingPixel (1L<<8) #define CWOverrideRedirect (1L<<9) #define CWSaveUnder (1L<<10) #define CWEventMask (1L<<11) #define CWDontPropagate (1L<<12) #define CWColormap (1L<<13) #define CWCursor (1L<<14) /* Values */ typedef struct { Pixmap background_pixmap; /* background, None, or ParentRelative */ unsigned long background_pixel; /* background pixel */ Pixmap border_pixmap; /* border of the window or CopyFromParent */ unsigned long border_pixel; /* border pixel value */ int bit_gravity; /* one of bit gravity values */ int win_gravity; /* one of the window gravity values */ int backing_store; /* NotUseful, WhenMapped, Always */ unsigned long backing_planes; /* planes to be preserved if possible */ unsigned long backing_pixel; /* value to use in restoring planes */ Bool save_under; /* should bits under be saved? (popups) */ long event_mask; /* set of events that should be saved */ long do_not_propagate_mask; /* set of events that should not propagate */ Bool override_redirect; /* boolean value for override_redirect */ Colormap colormap; /* color map to be associated with window */ Cursor cursor; /* cursor to be displayed (or None) */ } XSetWindowAttributes; For a detailed explanation of the members of this structure, see Xlib - C Language X Interface.
BadAlloc The server failed to allocate the requested resource or server memory. BadColor A value for a Colormap argument does not name a defined Colormap. BadCursor A value for a Cursor argument does not name a defined Cursor. BadMatch The values do not exist for an InputOnly window. BadMatch Some argument or pair of arguments has the correct type and range but fails to match in some other way required by the request. BadPixmap A value for a Pixmap argument does not name a defined Pixmap. BadValue Some numeric value falls outside the range of values accepted by the request. Unless a specific range is specified for an argument, the full range defined by the argument's type is accepted. Any argument defined as a set of alternatives can generate this error. BadWindow A value for a Window argument does not name a defined Window.
XChangeWindowAttributes(3), XConfigureWindow(3), XDefineCursor(3), XDestroyWindow(3), XMapWindow(3), XRaiseWindow(3), XUnmapWindow(3) Xlib - C Language X Interface
Personal Opportunity - Free software gives you access to billions of dollars of software at no cost. Use this software for your business, personal use or to develop a profitable skill. Access to source code provides access to a level of capabilities/information that companies protect though copyrights. Open source is a core component of the Internet and it is available to you. Leverage the billions of dollars in resources and capabilities to build a career, establish a business or change the world. The potential is endless for those who understand the opportunity.
Business Opportunity - Goldman Sachs, IBM and countless large corporations are leveraging open source to reduce costs, develop products and increase their bottom lines. Learn what these companies know about open source and how open source can give you the advantage.
Free Software provides computer programs and capabilities at no cost but more importantly, it provides the freedom to run, edit, contribute to, and share the software. The importance of free software is a matter of access, not price. Software at no cost is a benefit but ownership rights to the software and source code is far more significant.
Free Office Software - The Libre Office suite provides top desktop productivity tools for free. This includes, a word processor, spreadsheet, presentation engine, drawing and flowcharting, database and math applications. Libre Office is available for Linux or Windows.
The Free Books Library is a collection of thousands of the most popular public domain books in an online readable format. The collection includes great classical literature and more recent works where the U.S. copyright has expired. These books are yours to read and use without restrictions.
Source Code - Want to change a program or know how it works? Open Source provides the source code for its programs so that anyone can use, modify or learn how to write those programs themselves. Visit the GNU source code repositories to download the source.
Study at Harvard, Stanford or MIT - Open edX provides free online courses from Harvard, MIT, Columbia, UC Berkeley and other top Universities. Hundreds of courses for almost all major subjects and course levels. Open edx also offers some paid courses and selected certifications.
Linux Manual Pages - A man or manual page is a form of software documentation found on Linux/Unix operating systems. Topics covered include computer programs (including library and system calls), formal standards and conventions, and even abstract concepts.