XDrawLine
XDrawLine is a function within the X Window System's Xlib library used for drawing a line segment on a drawable surface. A drawable surface can be a window, a pixmap, or a similar graphical object. The function takes several arguments: the display connection, the destination drawable, the graphic context, and the coordinates of the line's start and end points. The coordinates are typically specified as integers representing the x and y positions relative to the drawable's origin. The graphic context, often referred to as GC, holds information about the line's appearance, such as its color, thickness, and line style (e.g., solid, dashed). XDrawLine is a fundamental routine for generating basic graphical primitives in X11 applications. It is part of the Xlib API, which provides a low-level interface to the X Window System protocol. Applications use XDrawLine to construct more complex graphical elements and user interfaces. The function itself is straightforward, but its effective use depends on correctly setting up the graphic context and providing accurate coordinates.