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Full Discussion: Unclear pointer and array
Top Forums Programming Unclear pointer and array Post 302884188 by Don Cragun on Saturday 18th of January 2014 08:14:10 AM
Old 01-18-2014
Try this instead:
Code:
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#define IOBufLen        100

char *substring(size_t start, size_t stop, const char *src, char *dst, size_t size)
{
    unsigned int count = stop - start;
    if (count >= --size) {
        count = size;
    }
    sprintf(dst, "%.*s", count, src + start);
    return dst;
}

int main(int argc, char **argv)
{
    char *text=(char*)malloc(IOBufLen);  //Line 40, change to text[100] will work
    char *a=(char*)malloc(IOBufLen);   //Line 41, change to a[100] will work
    int start, end;

    if (argc != 4) {
        printf("Error! Usage:\n\t \
argv[0]=program;\n\t \
argv[1]=input string\n\t \
argv[2]=start_position of string\n\t \
argv[3]=end_postion of string\n");

        return 1;
    }

    strncpy(text, argv[1], IOBufLen - 1); // -1 to be sure text is null terminated.
    start = atoi(argv[2]);
    end = atoi(argv[3]);

    printf("substring = \"%s\"\n", substring(start, end, text, a, IOBufLen));

    return 0;
}

Do you see why these changes make it work?
This User Gave Thanks to Don Cragun For This Post:
 

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glutInitWindowPosition(3GLUT)					       GLUT					     glutInitWindowPosition(3GLUT)

NAME
glutInitWindowPositionWindowPosition, glutInitWindowSize - set the initial window position and size respectively. SYNTAX
void glutInitWindowSize(int width, int height); void glutInitWindowPosition(int x, int y); ARGUMENTS
width Width in pixels. height Height in pixels. x Window X location in pixels. y Window Y location in pixels. DESCRIPTION
Windows created by glutCreateWindow will be requested to be created with the current initial window position and size. The initial value of the initial window position GLUT state is -1 and -1. If either the X or Y component to the initial window position is negative, the actual window position is left to the window system to determine. The initial value of the initial window size GLUT state is 300 by 300. The initial window size components must be greater than zero. The intent of the initial window position and size values is to provide a suggestion to the window system for a window's initial size and position. The window system is not obligated to use this information. Therefore, GLUT programs should not assume the window was created at the specified size or position. A GLUT program should use the window's reshape callback to determine the true size of the window. EXAMPLE
If you would like your GLUT program to default to starting at a given screen location and at a given size, but you would also like to let the user override these defaults via a command line argument (such as -geometry for X11), call glutInitWindowSize and glutInitWindowPosi- tion before your call to glutInit. For example: int main(int argc, char **argv) { glutInitWindowSize(500, 300); glutInitWindowPosition(100, 100); glutInit(&argc, argv); ... } However, if you'd like to force your program to start up at a given size, call glutInitWindowSize and glutInitWindowPosition after your call to glutInit. For example: int main(int argc, char **argv) { glutInit(&argc, argv); glutInitWindowSize(500, 300); glutInitWindowPosition(100, 100); ... } SEE ALSO
glutInit, glutCreateWindow, glutCreateSubWindow, glutReshapeFunc, glutGet AUTHOR
Mark J. Kilgard (mjk@nvidia.com) GLUT
3.7 glutInitWindowPosition(3GLUT)
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