Compiler error: memset was not declared in this scope

Question

I am trying to compile my C program in Ubuntu 9.10 (gcc 4.4.1).

I am getting this error:

Rect.cpp:344: error: ‘memset’ was not declared in this scope 

But the problem is I have already included in my cpp file:

#include <stdio.h> #include <stdlib.h> 

And the same program compiles fine under Ubuntu 8.04 (gcc 4.2.4).

Please tell me what am I missing.

Answer 1

You should include <string.h> (or its C++ equivalent, <cstring>).

Answer 2

Whevever you get a problem like this just go to the man page for the function in question and it will tell you what header you are missing, e.g.

$ man memset  MEMSET(3)                BSD Library Functions Manual                MEMSET(3)  NAME      memset -- fill a byte string with a byte value  LIBRARY      Standard C Library (libc, -lc)  SYNOPSIS      #include <string.h>       void *      memset(void *b, int c, size_t len); 

Note that for C++ it's generally preferable to use the proper equivalent C++ headers, <cstring>/<cstdio>/<cstdlib>/etc, rather than C's <string.h>/<stdio.h>/<stdlib.h>/etc.