int main(int argc, char *argv[])
{
    char line[MAXLINE];
    long lineno = 0;
    int c, except = 0, number = 0, found = 0;

    while(--argc > 0 && (*++argv)[0] == '-')
        while(c = *++argv[0])
            switch (c)
            {
                case 'x':
                    except = 1;
                    break;
                case 'n':
                    number = 1;
                    break;
                default:
                    printf("find: illegal option %c\n", c);
                    argc = 0;
                    found = -1;
                    break;                  
            }
    if(argc != 1)
        printf("Usage: find -x -n pattern\n");
    else
        while(getlines(line, MAXLINE) > 0)
        {
            lineno++;
            if((strstr(line, *argv) != NULL) != except)
            {
               if(number)
                    printf("%ld:", lineno);
               printf("%s", line);
               found++;
            }
        }
    return found;
}
返回found有什么意义，不是很明白。改成返回0也能正常运行

你说的我还是不明白