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CALLOC(3P)                 POSIX Programmer's Manual                CALLOC(3P)
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  suc-
       ceeds 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  allo-
       cated  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,  cal-
       loc() 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 Electri-
       cal  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.ker-
       nel.org/doc/man-pages/reporting_bugs.html .
IEEE/The Open Group                  2013                           CALLOC(3P)