man3/cfree.3

   1 .\" Copyright (c) 2003 Andries Brouwer (aeb@cwi.nl)
   2 .\"
   3 .\" SPDX-License-Identifier: GPL-2.0-or-later
   4 .\"
   5 .TH CFREE 3 2021-03-22 "Linux man-pages (unreleased)" "Linux Programmer's Manual"
   6 .SH NAME
   7 cfree \- free allocated memory
   8 .SH LIBRARY
   9 Standard C library
  10 .RI ( libc ", " \-lc )
  11 .SH SYNOPSIS
  12 .nf
  13 .PP
  14 .B "#include <stdlib.h>"
  15 .PP
  16 /* In SunOS 4 */
  17 .BI "int cfree(void *" ptr );
  18 .PP
  19 /* In glibc or FreeBSD libcompat */
  20 .BI "void cfree(void *" ptr );
  21 .PP
  22 /* In SCO OpenServer */
  23 .BI "void cfree(char *" ptr ", unsigned int " num ", unsigned int " size );
  24 .PP
  25 /* In Solaris watchmalloc.so.1 */
  26 .BI "void cfree(void *" ptr ", size_t " nelem ", size_t " elsize );
  27 .fi
  28 .PP
  29 .RS -4
  30 Feature Test Macro Requirements for glibc (see
  31 .BR feature_test_macros (7)):
  32 .RE
  33 .PP
  34 .BR cfree ():
  35 .nf
  36     Since glibc 2.19:
  37         _DEFAULT_SOURCE
  38     Glibc 2.19 and earlier:
  39         _BSD_SOURCE || _SVID_SOURCE
  40 .fi
  41 .SH DESCRIPTION
  42 This function should never be used.
  43 Use
  44 .BR free (3)
  45 instead.
  46 Starting with version 2.26, it has been removed from glibc.
  47 .SS 1-arg cfree
  48 In glibc, the function
  49 .BR cfree ()
  50 is a synonym for
  51 .BR free (3),
  52 "added for compatibility with SunOS".
  53 .PP
  54 Other systems have other functions with this name.
  55 The declaration is sometimes in
  56 .I <stdlib.h>
  57 and sometimes in
  58 .IR <malloc.h> .
  59 .SS 3-arg cfree
  60 Some SCO and Solaris versions have malloc libraries with a 3-argument
  61 .BR cfree (),
  62 apparently as an analog to
  63 .BR calloc (3).
  64 .PP
  65 If you need it while porting something, add
  66 .PP
  67 .in +4n
  68 .EX
  69 #define cfree(p, n, s) free((p))
  70 .EE
  71 .in
  72 .PP
  73 to your file.
  74 .PP
  75 A frequently asked question is "Can I use
  76 .BR free (3)
  77 to free memory allocated with
  78 .BR calloc (3),
  79 or do I need
  80 .BR cfree ()?"
  81 Answer: use
  82 .BR free (3).
  83 .PP
  84 An SCO manual writes: "The cfree routine is provided for compliance
  85 to the iBCSe2 standard and simply calls free.
  86 The num and size
  87 arguments to cfree are not used."
  88 .SH RETURN VALUE
  89 The SunOS version of
  90 .BR cfree ()
  91 (which is a synonym for
  92 .BR free (3))
  93 returns 1 on success and 0 on failure.
  94 In case of error,
  95 .I errno
  96 is set to
  97 .BR EINVAL :
  98 the value of
  99 .I ptr
 100 was not a pointer to a block previously allocated by
 101 one of the routines in the
 102 .BR malloc (3)
 103 family.
 104 .SH VERSIONS
 105 The
 106 .BR cfree ()
 107 function was removed
 108 .\" commit 025b33ae84bb8f15b2748a1d8605dca453fce112
 109 from glibc in version 2.26.
 110 .SH ATTRIBUTES
 111 For an explanation of the terms used in this section, see
 112 .BR attributes (7).
 113 .ad l
 114 .nh
 115 .TS
 116 allbox;
 117 lbx lb lb
 118 l l l.
 119 Interface       Attribute       Value
 120 T{
 121 .BR cfree ()
 122 T}      Thread safety   MT-Safe /* In glibc */
 123 .TE
 124 .hy
 125 .ad
 126 .sp 1
 127 .SH STANDARDS
 128 The 3-argument version of
 129 .BR cfree ()
 130 as used by SCO conforms to the iBCSe2 standard:
 131 Intel386 Binary Compatibility Specification, Edition 2.
 132 .SH SEE ALSO
 133 .BR malloc (3)