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C program to assign and copy hexadecimal values in character buffer.

By: IncludeHelp, On 04 OCT 2016

In this program we will learn how to assign and copy hexadecimal values into character buffer (string variable) in c programming language?

Here we will learn, how we can declare an unsigned char[] by assigning Hexadecimal values and how we can copy Buffer with Hexadecimal values using memcpy() into character buffer (string variable).

What is memcpy()?

memcpy() – it is a library function declared in string.h which copies memory area (a fixed number of bytes) from one buffer to another buffer.

Read about more memcpy()

Syntax

void *memcpy(void *dest, const void *src, size_t n);

void *dest - Destination buffer pointer

void *src - Source buffer pointer

size_t n - Number of bytes to copy

C program (Code snippet) – To Assign and Copy Hexadecimal values in Character Buffer (String)

Let’s consider the following example:

/*C program to assign and copy hexadecimal 
values in character buffer.*/

#include <stdio.h>
#include <string.h>

int main(){
	//through assignment
	unsigned char hexV[]={0x05,0x0A,0xAF,0xFE,0x23};	
	int loop;
	
	printf("Values through assigning...\n");
	for(loop=0; loop<5; loop++){
		printf("hexV[%d] : %02X\n",loop,hexV[loop]);
	}
	
	//through copy
	memcpy(hexV,"\x10\xAA\x20\xFA\xAF",5);
	
	printf("Values through copying...\n");
	for(loop=0; loop<5; loop++){
		printf("hexV[%d] : %02X\n",loop,hexV[loop]);
	}
	
	return 0;
}

Output

            Values through assigning... 
            hexV[0] : 05
            hexV[1] : 0A
            hexV[2] : AF
            hexV[3] : FE
            hexV[4] : 23
            Values through copying... 
            hexV[0] : 10
            hexV[1] : AA
            hexV[2] : 20
            hexV[3] : FA
            hexV[4] : AF