free

FREE(3POSIX)               POSIX Programmer's Manual              FREE(3POSIX)



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
       free — free allocated memory

SYNOPSIS
       #include <stdlib.h>

       void free(void *ptr);

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 free() function shall cause the space pointed to by ptr to be
       deallocated; that is, made available for further allocation. If ptr is
       a null pointer, no action shall occur. Otherwise, if the argument does
       not match a pointer earlier returned by a function in POSIX.1‐2008 that
       allocates memory as if by malloc(), or if the space has been
       deallocated by a call to free() or realloc(), the behavior is
       undefined.

       Any use of a pointer that refers to freed space results in undefined
       behavior.

RETURN VALUE
       The free() function shall not return a value.

ERRORS
       No errors are defined.

       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
       calloc(), malloc(), posix_memalign(), 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                         FREE(3POSIX)