char date1[8] = “June 14”;

char date1[] = “June 14”;

char date1[8] = {‘J’, ‘u’, ‘n’, ‘e’, ‘ ’, ‘1’, ‘4’, ‘\0’};

char date1[] = {‘J’, ‘u’, ‘n’, ‘e’, ‘ ’, ‘1’, ‘4’, ‘\0’};

char *str = “June 14”;

#include<stdio.h>

#include<string.h>

int main(){

char str1[8] = "June 14";

char str2[] = "June 14";

char str3[8] = {'J', 'u', 'n', 'e', ' ', '1', '4', '\0'};

char str4[] = {'J', 'u', 'n', 'e', ' ', '1', '4', '\0'};

char *str5 = "June 14";

printf("Length of str%d is [%zu].\n", 1, strlen(str1));

printf("Length of str%d is [%zu].\n", 2, strlen(str2));

printf("Length of str%d is [%zu].\n", 3, strlen(str3));

printf("Length of str%d is [%zu].\n", 4, strlen(str4));

printf("Length of str%d is [%zu].\n\n", 5, strlen(str5));

printf("Size of str%d is [%zu].\n", 1, sizeof(str1));

printf("Size of str%d is [%zu].\n", 2, sizeof(str2));

printf("Size of str%d is [%zu].\n", 3, sizeof(str3));

printf("Size of str%d is [%zu].\n", 4, sizeof(str4));

printf("Size of str%d is [%zu].\n", 5, sizeof(str5));

}

Create a node:

• Write a method that creates a new node with the give data and the address.

• Make your method safe (for the case when malloc fails!)

if(newNode == NULL)

{

printf("Error: malloc failed!\n");

exit(0);

}

• Call this method in your main() and make sure it works fine!

/*

This method creates a new node based on the

the data and the pointer to the next node.

It returns the newly created node (pointer).

*/

node* createNode(int data, node* next)

{

node* newNode = (node*)malloc(sizeof(node));

newNode->data = data;

newNode->next = next;

return newNode;

}

What is a HEAD?

We have defined a new concept called a NODE,

But

we did NOT define the Linked List!?

How can we have access to its elements then?!

/**

* This method initializes a linked list by

* creating a new node and setting the head

* to point to this node.

*

* It returns a pointer to the head

*/

node* initializeList(node* head, int data)

{

node* newNode = createNode(data,head);

head = newNode;

return head;

}

DESCRIPTION:

The fopen() function opens the file whose name is the string pointed to by path and associates a stream with it.

The argument mode points to a string beginning with one of the following sequences (possibly followed by additional characters, as described below):

• r Open text file for reading. The stream is positioned at the beginning of the file.

• r+ Open for reading and writing. The stream is positioned at the beginning of the file.

• w Truncate file to zero length or create text file for writing. The stream is positioned at the beginning of the file.

• w+ Open for reading and writing. The file is created if it does not exist, otherwise it is truncated. The stream is positioned at the beginning of the file.

• a Open for appending (writing at end of file). The file is created if it does not exist. The stream is positioned at the end of the file.

• a+ Open for reading and appending (writing at end of file). The file is created if it does not exist. The initial file position for reading is at the beginning of the file, but output is always appended to the end of the file.

DESCRIPTION:

close() closes the file descriptor fd, so that it no longer refers to any file and may be reused.

NOTE:

Not checking the return value of close() is a common but nevertheless serious programming error.

//Reading from file, in chuncks of size 1024

#include <stdio.h>

#include <string.h>

#include <errno.h>

#define BUFSIZE 1024

int main(){

char buf[BUFSIZE];

FILE *f;

size_t nread;

f = fopen("lab6.c", "r");

if(f){

while((nread = fread(buf, 1, sizeof buf, f)) > 0)

fwrite(buf, 1, nread, stdout);

if(ferror(f)) {

//Do something with the error

return 0;

}

fclose(f);

}

return 0;

}

• Modify your code such that it read a text file like the one on the right, and prints out only the EVEN numbers.

• Yes, the file contains NUMBERS only.

• Yes, there is one number in each line.

SAMPLE FILE:

12

44

23

77

1

9

561

234