개요

• 솔라나라에 설명된 어플리케이션에 대해 맨 페이지를 찾아 출력한다.
• MAN 페이지에 대한 설명은 윈디하나의 솔라나라: MAN 페이지을 참고하자.
• svcadm(8)을 검색하려면 섹션에서 8 을 선택하고, 맨 페이지 이름에 svcadm을 입력하고 검색을 누른다.

posix_madvise(3)

POSIX_MADVISE(3)           Linux Programmer's Manual          POSIX_MADVISE(3)

NAME
       posix_madvise - give advice about patterns of memory usage

SYNOPSIS
       #include <sys/mman.h>

       int posix_madvise(void *addr, size_t len, int advice);

   Feature Test Macro Requirements for glibc (see feature_test_macros(7)):

       posix_madvise():
           _POSIX_C_SOURCE >= 200112L

DESCRIPTION
       The posix_madvise() function allows an application to advise the system
       about  its  expected  patterns  of usage of memory in the address range
       starting at addr and continuing for len bytes.  The system is  free  to
       use  this advice in order to improve the performance of memory accesses
       (or to ignore the advice altogether), but calling posix_madvise() shall
       not affect the semantics of access to memory in the specified range.

       The advice argument is one of the following:

       POSIX_MADV_NORMAL
              The application has no special advice regarding its memory usage
              patterns for the specified address range.  This is  the  default
              behavior.

       POSIX_MADV_SEQUENTIAL
              The  application  expects  to access the specified address range
              sequentially, running from lower addresses to higher  addresses.
              Hence,  pages in this region can be aggressively read ahead, and
              may be freed soon after they are accessed.

       POSIX_MADV_RANDOM
              The application expects to access the  specified  address  range
              randomly.  Thus, read ahead may be less useful than normally.

       POSIX_MADV_WILLNEED
              The application expects to access the specified address range in
              the near future.  Thus, read ahead may be beneficial.

       POSIX_MADV_DONTNEED
              The  application  expects  that it will not access the specified
              address range in the near future.

RETURN VALUE
       On success, posix_madvise() returns 0.  On failure, it returns a  posi‐
       tive error number.

ERRORS
       EINVAL addr  is  not a multiple of the system page size or len is nega‐
              tive.

       EINVAL advice is invalid.

       ENOMEM Addresses in the specified range  are  partially  or  completely
              outside the caller's address space.

VERSIONS
       Support for posix_madvise() first appeared in glibc version 2.2.

CONFORMING TO
       POSIX.1-2001.

NOTES
       POSIX.1 permits an implementation to generate an error if len is 0.  On
       Linux, specifying len as 0 is permitted (as a successful no-op).

       In  glibc,  this  function  is  implemented using madvise(2).  However,
       since glibc 2.6, POSIX_MADV_DONTNEED is treated as a no-op, because the
       corresponding madvise(2) value, MADV_DONTNEED, has  destructive  seman‐
       tics.

SEE ALSO
       madvise(2), posix_fadvise(2)

COLOPHON
       This  page  is  part of release 5.02 of the Linux man-pages project.  A
       description of the project, information about reporting bugs,  and  the
       latest     version     of     this    page,    can    be    found    at
       https://www.kernel.org/doc/man-pages/.

Linux                             2017-09-15                  POSIX_MADVISE(3)