Here signal handler is defined but I need to use it in the main program I did not see the function is used. Can you help to correct this code

#include

#include

#include

#include

#include

#include

#include

#include

#include

#include

// This is a structure class that is used to read data from

// the file where character as letter and short integer as the the number

struct pairs

{

char letter;

short int number;

};

// Function to count the number of set bits in a binary representation

int count_set_bits(int num1)

{

int count = 0;

while (num1)

{

count += num1 & 1; // Doing bit-wise comparision with the AND (&) Operator and the number 1

num1 >>= 1; // The binary bit shifts to the right by one digit

}

return count;

}

void timer_handler(int sig)

{

printf("Timer expired. Exiting program. ");

exit(0);

}

int main()

{

char c;

int num;

FILE *file1; // This is where the FILE *file pointer is used to access the file

struct pairs char_int; // We are declaring char_int as the structure

file1 = fopen("error.dat", "rb"); // The file image.dat is being opened and assigned the

// pointer to File 1

if(!file1) // This is a if-condition loop to check if error occurs while opening file

{

printf("File cannot be opened or found ");

return 1;

}

struct sigaction sa;

memset(&sa, 0, sizeof(sa));

sa.sa_handler = &timer_handler;

sigaction(SIGALRM, &sa, NULL);

// Set timer for 60 seconds

alarm(60);

// Read a character-integer pair every second

while (fread(&char_int, sizeof(struct pairs), 1, file1))

{

// Compute the parity of the pair

c = char_int.letter;

num = char_int.number;

int parity = count_set_bits(c) + count_set_bits(num); // Adding counting number of bits set to 1 in both char and integer

if (parity % 2 == 0) // Checking if parity is even using % operator

{

// If parity is even, the data is valid

int original_num = num;

printf("(%c, %d) ",c ,original_num); // This will give the original value of the character and pr

for (int i = 0; i < char_int.number; i++) // This loop is used to display the decoded form of the pairing of character and integer

// by printing the character so many times until it reaches the value of the integer

// It will start from 0 and continues until i is less than integer

{

printf("%c", char_int.letter); // This print function is used to print the character

// retrieved from the file

}

printf(" "); // Each record is printed on a new line

}

else

{

// The parity is odd, so the data is corrupted

printf("Error: Odd parity ");

}

sleep(1); // This uses a sleep system call for the specified number of seconds until interrupted

// Reading 1 character integer pair every second here 1 corresponds to every second

}

fclose(file1); // Closing the file after successfully reading the data

return 0;

}

``