gen/malloc_size.3

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  21 .Dd May 23, 2006
  22 .Dt MALLOC_SIZE 3
  23 .Os
  24 .Sh NAME
  25 .Nm malloc_good_size ,
  26 .Nm malloc_size
  27 .Nd memory allocation information
  28 .Sh SYNOPSIS
  29 .In malloc/malloc.h
  30 .Ft size_t
  31 .Fo malloc_good_size
  32 .Fa "size_t size"
  33 .Fc
  34 .Ft size_t
  35 .Fo malloc_size
  36 .Fa "const void *ptr"
  37 .Fc
  38 .Sh DESCRIPTION
  39 The
  40 .Fn malloc_size
  41 function returns the size of the memory block
  42 that backs the allocation pointed to by
  43 .Fa ptr .
  44 The memory block size is always at least as large
  45 as the allocation it backs, and may be larger.
  46 .Pp
  47 The
  48 .Fn malloc_good_size
  49 function rounds
  50 .Fa size
  51 up to a value that the allocator implementation can allocate
  52 without adding any padding;
  53 it then returns that rounded-up value.
  54 .Sh SEE ALSO
  55 .Xr malloc 3