stdlib/memory.3

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  32 .\"     @(#)memory.3    8.1 (Berkeley) 6/4/93
  33 .\" $FreeBSD: src/lib/libc/stdlib/memory.3,v 1.11 2001/09/07 14:46:35 asmodai Exp $
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  35 .Dd June 4, 1993
  36 .Dt MEMORY 3
  37 .Os
  38 .Sh NAME
  39 .Nm alloca ,
  40 .Nm calloc ,
  41 .Nm free ,
  42 .Nm malloc ,
  43 .Nm mmap ,
  44 .Nm realloc
  45 .Nd general memory allocation operations
  46 .Sh LIBRARY
  47 .Lb libc
  48 .Sh SYNOPSIS
  49 .In stdlib.h
  50 .Ft void *
  51 .Fo alloca
  52 .Fa "size_t size"
  53 .Fc
  54 .Ft void *
  55 .Fo calloc
  56 .Fa "size_t nelem"
  57 .Fa "size_t elsize"
  58 .Fc
  59 .Ft void
  60 .Fo free
  61 .Fa "void *ptr"
  62 .Fc
  63 .Ft void *
  64 .Fo malloc
  65 .Fa "size_t size"
  66 .Fc
  67 .Ft void *
  68 .Fo realloc
  69 .Fa "void *ptr"
  70 .Fa "size_t size"
  71 .Fc
  72 .In sys/mman.h
  73 .Ft void *
  74 .Fo mmap
  75 .Fa "void * addr"
  76 .Fa "size_t len"
  77 .Fa "int prot"
  78 .Fa "int flags"
  79 .Fa "int fildes"
  80 .Fa "off_t off"
  81 .Fc
  82 .Sh DESCRIPTION
  83 These functions allocate and free memory for the calling process.
  84 They are described in the
  85 individual manual pages.
  86 .Sh LEGACY SYNOPSIS
  87 .Fd #include <sys/types.h>
  88 .Fd #include <sys/mman.h>
  89 .Pp
  90 .Ft void *
  91 .br
  92 .Fo mmap
  93 .Fa "void * addr"
  94 .Fa "size_t len"
  95 .Fa "int prot"
  96 .Fa "int flags"
  97 .Fa "int fildes"
  98 .Fa "off_t off"
  99 .Fc ;
 100 .Pp
 101 The include file
 102 .In sys/types.h
 103 is needed for this function.
 104 .Sh COMPATIBILITY
 105 .Fn mmap
 106 now returns with
 107 .Va errno
 108 set to EINVAL in places that historically succeeded.
 109 The rules have changed as follows:
 110 .Bl -bullet
 111 .It
 112 The
 113 .Fa flags
 114 parameter must specify either MAP_PRIVATE or MAP_SHARED.
 115 .It
 116 The
 117 .Fa size
 118 parameter must not be 0.
 119 .It
 120 The
 121 .Fa off
 122 parameter must be a multiple of pagesize,
 123 as returned by
 124 .Fn sysconf .
 125 .El
 126 .Sh SEE ALSO
 127 .Xr mmap 2 ,
 128 .Xr alloca 3 ,
 129 .Xr calloc 3 ,
 130 .Xr free 3 ,
 131 .Xr malloc 3 ,
 132 .Xr realloc 3 ,
 133 .Xr compat 5
 134 .Sh STANDARDS
 135 These functions, with the exception of
 136 .Fn alloca
 137 and
 138 .Fn mmap
 139 conform to
 140 .St -isoC .