Advises the system of expected paging behavior.
Standard C Library (libc.a).
#include <sys/types.h> #include <sys/mman.h>
int madvise( addr, len, behav)
caddr_t addr;
size_t len;
int behav;
The madvise subroutine permits a process to advise the system about its expected future behavior in referencing a mapped file region or anonymous memory region.
The madvise subroutine has no functionality and is supported for compatibility only.
addr | Specifies the starting address of the memory region. Must be a multiple of the page size returned by the sysconf subroutine using the _SC_PAGE_SIZE value for the Name parameter. |
len | Specifies the length, in bytes, of the memory region. If the len value is not a multiple of page size as returned by the sysconf subroutine using the _SC_PAGE_SIZE value for the Name parameter, the length of the region will be rounded up to the next multiple of the page size. |
behav | Specifies the future behavior of the memory region. The following
values for the behav parameter are defined in the /usr/include/sys/mman.h file:
|
When successful, the madvise subroutine returns 0. Otherwise, it returns -1 and sets the errno global variable to indicate the error.
If the madvise subroutine is unsuccessful, the errno global variable can be set to one of the following values:
EINVAL | The behav parameter is invalid. |
ENOSPC | The behav parameter specifies MADV_SPACEAVAIL and resources cannot be reserved. |
The mmap (mmap or mmap64 Subroutine) subroutine, sysconf subroutine.
List of Memory Manipulation Services and Understanding Paging Space Programming Requirements in AIX 5L Version 5.2 General Programming Concepts: Writing and Debugging Programs.