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memcmp
Syntax:
  #include <string.h>
  int memcmp( const void *buffer1, const void *buffer2, size_t count );

The function memcmp() compares the first count characters of buffer1 and buffer2. The return values are as follows:

Value Explanation
less than 0 buffer1 is less than buffer2
equal to 0 buffer1 is equal to buffer2
greater than 0 buffer1 is greater than buffer2