FFI::memcmp
(PHP 7 >= 7.4.0, PHP 8)
FFI::memcmp — Compares memory areas
說明
   Compares size bytes from the memory areas ptr1 and
   ptr2. Both ptr1 and ptr2
   can be any native data structures (FFI\CData) or PHP
   strings.
  
參數
- 
ptr1
- 
     The start of one memory area. 
- 
ptr2
- 
     The start of another memory area. 
- 
size
- 
     The number of bytes to compare. 
返回值
   Returns < 0 if the contents of the memory area starting at ptr1
   are considered less than the contents of the memory area starting at ptr2,
   > 0 if the contents of the first memory area are considered greater than the second,
   and 0 if they are equal.