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MEMORY(3)                BSD Library Functions Manual                MEMORY(3)

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:

     oo   The flags parameter must specify either MAP_PRIVATE or MAP_SHARED.

     oo   The size parameter must not be 0.

     oo   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'').

BSD                              June 4, 1993                              BSD