Chapter 2.1, Problem 2.7PP

Program Plan Intro

String representation:

• A string is encoded by an array of characters ended by the null character.
• Each character is indicated by some standard encoding.
  • The most character occurs with ACSII code.
  • Therefore, if the user execute the function “show_bytes” with arguments “12345”, then the user gets the result of 31 32 33 34 35

From the given question, the function definition for “show_bytes” is

void show_bytes(byte_pointer start, size_t len) {

int i;

for (i = 0; i < len; i++)

printf(" %.2x ", start[i]);

printf(“\n”);

}

The above function is used for show the bytes in hexadecimal.

• The “byte_pointer” is a pointer to an object of type unsigned char.
• The data type of “size_t” represents the size of data.
• In the printing statement, “%.2x” represents that an integer should be showed in hexadecimal with at least 2 digits.