PROLOG

       This  manual  page  is part of the POSIX Programmer's Manual.  The Linux implementation of this interface
       may differ (consult the corresponding Linux manual page for details of Linux behavior), or the  interface
       may not be implemented on Linux.

NAME

       calloc — a memory allocator

SYNOPSIS

       #include <stdlib.h>

       void *calloc(size_t nelem, size_t elsize);

DESCRIPTION

       The  functionality  described  on  this  reference  page is aligned with the ISO C standard. Any conflict
       between the requirements described  here  and  the  ISO C  standard  is  unintentional.  This  volume  of
       POSIX.1‐2008 defers to the ISO C standard.

       The  calloc()  function  shall allocate unused space for an array of nelem elements each of whose size in
       bytes is elsize.  The space shall be initialized to all bits 0.

       The order and contiguity of storage allocated by successive calls to calloc() is unspecified. The pointer
       returned if the allocation succeeds shall be suitably aligned so that it may be assigned to a pointer  to
       any  type  of  object  and  then  used  to access such an object or an array of such objects in the space
       allocated (until the space is explicitly freed or  reallocated).  Each  such  allocation  shall  yield  a
       pointer  to  an  object  disjoint  from  any  other object. The pointer returned shall point to the start
       (lowest byte address) of the allocated space. If the space cannot be allocated, a null pointer  shall  be
       returned.  If  the  size  of  the space requested is 0, the behavior is implementation-defined: the value
       returned shall be either a null pointer or a unique pointer.

RETURN VALUE

       Upon successful completion with both nelem and elsize non-zero, calloc() shall return a  pointer  to  the
       allocated  space.  If  either  nelem or elsize is 0, then either a null pointer or a unique pointer value
       that can be successfully passed to free() shall be returned. Otherwise, it shall return  a  null  pointer
       and set errno to indicate the error.

ERRORS

       The calloc() function shall fail if:

       ENOMEM Insufficient memory is available.

       The following sections are informative.

EXAMPLES

       None.

APPLICATION USAGE

       There is now no requirement for the implementation to support the inclusion of <malloc.h>.

RATIONALE

       None.

FUTURE DIRECTIONS

       None.

SEE ALSO

       free(), malloc(), realloc()

       The Base Definitions volume of POSIX.1‐2008, <stdlib.h>

COPYRIGHT

       Portions of this text are reprinted and reproduced in electronic form from IEEE Std 1003.1, 2013 Edition,
       Standard  for  Information Technology -- Portable Operating System Interface (POSIX), The Open Group Base
       Specifications Issue 7, Copyright (C) 2013 by the Institute of Electrical and Electronics Engineers,  Inc
       and  The  Open Group.  (This is POSIX.1-2008 with the 2013 Technical Corrigendum 1 applied.) In the event
       of any discrepancy between this version and the original IEEE and The Open Group Standard,  the  original
       IEEE and The Open Group Standard is the referee document. The original Standard can be obtained online at
       http://www.unix.org/online.html .

       Any  typographical  or formatting errors that appear in this page are most likely to have been introduced
       during  the  conversion  of  the  source  files  to  man  page  format.  To  report  such   errors,   see
       https://www.kernel.org/doc/man-pages/reporting_bugs.html .

IEEE/The Open Group                                   2013                                        CALLOC(3POSIX)