Skip to content
Related Articles
Open in App
Not now

Related Articles

memcpy() in C/C++

Improve Article
Save Article
Like Article
  • Difficulty Level : Basic
  • Last Updated : 06 Sep, 2021
Improve Article
Save Article
Like Article

memcpy() is used to copy a block of memory from a location to another. It is declared in string.h

// Copies "numBytes" bytes from address "from" to address "to"
void * memcpy(void *to, const void *from, size_t numBytes);

Below is a sample C program to show working of memcpy().


/* A C program to demonstrate working of memcpy */
#include <stdio.h>
#include <string.h>
int main ()
  char str1[] = "Geeks"
  char str2[] = "Quiz"
  puts("str1 before memcpy ");
  /* Copies contents of str2 to str1 */
  memcpy (str1, str2, sizeof(str2));
  puts("\nstr1 after memcpy ");
  return 0;


str1 before memcpy 

str1 after memcpy 

1) memcpy() doesn’t check for overflow or \0 
2) memcpy() leads to problems when source and destination addresses overlap. 

memmove() is another library function that handles overlapping well.
Write your own memcpy() and memmove()
Please write comments if you find anything incorrect, or you want to share more information about the topic discussed above

My Personal Notes arrow_drop_up
Like Article
Save Article
Related Articles

Start Your Coding Journey Now!