Visual Studio error: 'strcpy_s': too few arguments for call

Question

I have run following C code in the Code::Blocks IDE and it worked properly without a problem. I tried compiling this code in Visual Studio 2015, and I got this error:

'strcpy_s': too few arguments for call

How can I fix this with minimal changes to my code? Here's the code:

#include<conio.h>
#include<stdio.h>
#include<string.h>
int main() {
    char string [81];
    int position;
    printf("type a string :");
    gets(string);
    printf("enter position for delete character :");
    scanf_s("%d", &position);
    strcpy_s(&string [position], &string [position + 1]);
    printf("the result string is: ");
    puts(string);
    _getch();
    return 0;
}

Code::Blocks can run this code and gives me the correct output, but Visual Studio does not! What can I do?

Answer 1

You are using strcpy_s, which is a specialized version of strcpy that does additional error checking and wants exactly 3 arguments:

errno_t strcpy_s(char *dest, rsize_t dest_size, const char *src);

I suppose you don't really need this. Use the standard strcpy function instead:

strcpy(&string[position], &string[position + 1]);

NOTE: same goes for scanf_s, use scanf instead if you don't have a good reason why scanf_s might be more useful to you.

As per why Code::Blocks compiles your code, well, it's probably just generating a warning instead of an error that aborts compilation.

---

Okay, turns out MSVC is particularly pedantic about this and doesn't like good ol' (faster and simpler) standard functions.

I changed to strcpy but Visual studio gives me this error now: 'strcpy': This function or variable may be unsafe. Consider using strcpy_s instead. To disable deprecation, use _CRT_SECURE_NO_WARNINGS. See online help for details.

You have two options:

1. Disable the check, see this related question and answer: How to use _CRT_SECURE_NO_WARNINGS.

   Basically just add this at the very top of your file (before any #include):

   #define _CRT_SECURE_NO_WARNINGS
   

2. Use strcpy_s in the proper way (also, check that position < strlen(string) first, otherwise your replacement is invalid):

   strcpy(&string[position], 81 - position, &string[position + 1]);
   

   And don't forget to check the return value!

---

Finally, while we are at it, using gets(string) is ALWAYS wrong. Never use gets(). Really surprised MSVC does not warn you about this. Use fgets instead:

fgets(string, 81, stdin);