NAME
alloca, calloc,
free, malloc,
mmap, realloc —
general memory allocation
operations
LIBRARY
Standard C Library (libc, -lc)
SYNOPSIS
#include
<stdlib.h>
void *
alloca(size_t size);
void *
calloc(size_t nelem,
size_t elsize);
void
free(void *ptr);
void *
malloc(size_t size);
void *
realloc(void *ptr,
size_t size);
#include
<sys/mman.h>
void *
mmap(void * addr,
size_t len, int prot,
int flags, int fildes,
off_t off);
DESCRIPTION
These functions allocate and free memory for the calling process. They are described in the individual manual pages.
LEGACY SYNOPSIS
#include
<sys/types.h> #include
<sys/mman.h>
void *
mmap(void
* addr, size_t len, int
prot, int flags, int
fildes, off_t off);;
The include file
<sys/types.h> is needed for
this function.
COMPATIBILITY
mmap() now returns with
errno set to EINVAL in places that historically
succeeded. The rules have changed as follows:
- The flags parameter must specify either MAP_PRIVATE or MAP_SHARED.
- The size parameter must not be 0.
- The off parameter must be a multiple of pagesize, as
returned by
sysconf().
SEE ALSO
mmap(2), alloca(3), calloc(3), free(3), malloc(3), realloc(3), compat(5)
STANDARDS
These functions, with the exception of
alloca() and mmap() conform
to ISO/IEC 9899:1990
(“ISO C90”).