memory leak in c/c++

[gauravdatir]

Is it necessary to mach the count of malloc() and free() in your C program to avoid memory leaks.?
If number of malloc() and free() are not equal then would it result in memory leak always ??

[JLBorges]

You need to also account for calloc() and realloc() (and strdup()).

#include <stdlib.h>

void foo()
{
    void* p1 = realloc( NULL, 100 ) ;
    void* p2 = calloc( 10, 10 ) ;
    // leak 
}

void bar()
{
    void* p = malloc(100) ;
    if(p) realloc( p, 0 ) ;
    // no leak 
}