realloc() -- General Function (libc)

Reallocate dynamic memory
#include <stdlib.h>
char *realloc(ptr, size)
char *ptr; unsigned size;

realloc() helps you  manage a program's arena.  It returns  a block of size
bytes that  holds the contents of  the old block, up to  the smaller of the
old and new sizes.  realloc() tries  to return the same block, truncated or
extended; if size is smaller than the size of the old block, realloc() will
return the same ptr.

If ptr is set to NULL, realloc() behaves like malloc().

Example

For an example of this function, see the entry for calloc().

See Also

alloca(),
arena,
calloc(),
free(),
libc,
malloc(),
memok(),
setbuf(),
stdlib.h
ANSI Standard, §7.10.3.4
POSIX Standard, §8.1

Diagnostics

realloc() returns  NULL if insufficient  memory is available.   It prints a
message  and  calls  abort()  if  it  discovers that  the  arena  has  been
corrupted,  which  most often  occurs  by  storing past  the  bounds of  an
allocated block.   realloc() behaves  unpredictably if handed  an incorrect
ptr.

© 2012 by Stephen A. Ness