balaji06nitc

 Profile Answers by balaji06nitc 

• Jun 18th, 2008

 

strcpy is meant to copy only null-terminated strings. It is probably
: implemented to copy every byte until it encounters a #0.
: memcpy can copy any memory location. It is not bound by a
: null-terminated string. Since memcpy cannot determine the size of
: the data to be copied, it needs the programmer to provide that
: information.


That is correct. Note that there is also a function called strncpy() which copies n bytes. It is almost identical to memcpy(), with the difference that it adds null termination at the end of the target string.

janhavibend

 Profile Answers by janhavibend Questions by janhavibend

• Jul 14th, 2008

 

when I checked with strncpy and memcpy both are not terminating string with '' after copying when dst size is less than src size. otherwise both will terminate dst string with '' when sizeof(dst) >= sizeof(src)

jca_dips

 Profile Answers by jca_dips 

• Jul 18th, 2008

 

strncpy copies upto null or specified no. of bytes, whichever is less. But memcpy overlooks null, and copies all specified no. of bytes. 
None of them adds null in destination string by itself. 

#include<conio.h>
#include<memory.h>
#include<string.h>

void main()
{
 char str1[50] = "This is india: a wonderful country";
    char str2[30];
 
 printf("%s",str1);
 strncpy(str2,str1,15);
 //memcpy(str2,str1,15);
 //str2[12] = '';
 printf("n%s",str2);
 printf("n%c%c",str2[12],str2[13]);

 getch();

} 

str1[8] is null. As strncpy copies upto null, str[12] and str[13] takes value as blank.
In case of memcpy as all the specifed 15 bytes are copied in the destination string,
str[12] takes 'i' and str[13] takes 'a' as values.