XLIB Programming Manual, Rel. 5, Third Edition

14.3 The Main of basecalc

The main is a very short and straightforward outline for the major routines to follow.

Example 14-2. basecalc — the main

char myDisplayName[256];
/* X11 Integer Programmer's Calculator with base conversions */
main (argc, argv)
int argc;
register char *argv[];
{
    /* So we can use the resource manager data merging functions */
    XrmInitialize();
    /* Parse command line first so we can open display, store any
     * options in a database */
    parseOpenDisp (&argc, argv);
    /* Get server defaults, program defaults, .Xdefaults;
     * merge them and finally the command line */
    mergeDatabases();
    /* Extract values from database and convert to form usable
     * by this program */
    extractOpts ();
    /* Load font, make pixmaps, set up arrays of windows */
    initCalc ();

    /* Get keyboard settings for interrupt, delete, etc. */
    initTty ();

    /* Make a standard cursor */
    makeCursor ();

    /* Set standard properties, create and map windows */
    makeWindows (argc, argv);

    /* Get events */
    takeEvents ();

    /* Bow out gracefully */
    XCloseDisplay(display);
    exit (1);
}

initTty is not shown in this chapter, but it is included in Appendix D. It simply performs a few system calls to determine which keys are being used for erase, delete, and interrupt.

The following sections describe each routine called in the main. Each section will begin with a brief description of the routine, followed by the declarations from basecalc.h that are needed with that routine and then the code.