The OpenNET Project / Index page

[ новости /+++ | форум | wiki | теги | ]

Интерактивная система просмотра системных руководств (man-ов)

 ТемаНаборКатегория 
 
 [Cписок руководств | Печать]

VOP_GETEXTATTR ()
  • >> VOP_GETEXTATTR (9) ( FreeBSD man: Ядро )

  • BSD mandoc
     

    NAME

    VOP_GETEXTATTR
    
     - retrieve named extended attribute from a vnode
    
     
    

    SYNOPSIS

       #include <sys/param.h>
       #include <sys/vnode.h>
       #include <sys/extattr.h>
    int Fo VOP_GETEXTATTR Fa struct vnode *vp Fa int attrnamespace Fa const char *name Fa struct uio *uio Fa size_t *size Fa struct ucred *cred Fa struct thread *td Fc  

    DESCRIPTION

    This vnode call may be used to retrieve a specific named extended attribute from a file or directory.

    Its arguments are:

    Fa vp
    The vnode of the file or directory.
    Fa attrnamespace
    Integer constant indicating which extended attribute namespace the attribute name is present in.
    Fa name
    Pointer to a null-terminated character string containing the attribute name.
    Fa uio
    The location of the data to be read.
    Fa size
    If not NULL on return it will contain the number of bytes required to read all of the attribute data. In most cases Fa uio will be NULL when Fa size is not, and vise versa.
    Fa cred
    The user credentials to use in authorizing the request.
    Fa td
    The thread requesting the extended attribute.

    The Fa cred pointer may be NULL to indicate that access control checks are not to be performed, if possible. This Fa cred setting might be used to allow the kernel to authorize extended attribute retrieval that the active process might not be permitted to do.

    Extended attribute semantics may vary by file system implementing the call. More information on extended attributes may be found in extattr(9).  

    LOCKS

    The vnode will be locked on entry and should remain locked on return.  

    RETURN VALUES

    On success, zero will be returned, and the uio structure will be updated to reflect data read. Otherwise, an appropriate error code is returned.  

    ERRORS

    Bq Er ENOATTR
    The requested attribute was not defined for this vnode.
    Bq Er EACCES
    The the caller does not have the appropriate privilege.
    Bq Er ENXIO
    The request was not valid in this file system for the specified vnode and attribute name.
    Bq Er ENOMEM
    Sufficient memory is not available to fulfill the request.
    Bq Er EFAULT
    The uio structure refers to an invalid userspace address.
    Bq Er EINVAL
    The Fa name , Fa namespace, or Fa uio argument is invalid.
    Bq Er EOPNOTSUPP
    The file system does not support VOP_GETEXTATTR (.);

     

    SEE ALSO

    extattr(9), vnode(9), VOP_LISTEXTATTR9, VOP_SETEXTATTR9  

    BUGS

    By passing in the empty string as the attribute name, some file systems will return a list of defined names on the target vnode for the requested namespace. This is a bad API, and will be replaced by an explicit VOP.


     

    Index

    NAME
    SYNOPSIS
    DESCRIPTION
    LOCKS
    RETURN VALUES
    ERRORS
    SEE ALSO
    BUGS


    Поиск по тексту MAN-ов: 




    Спонсоры:
    PostgresPro
    Inferno Solutions
    Hosting by Hoster.ru
    Хостинг:

    Закладки на сайте
    Проследить за страницей
    Created 1996-2022 by Maxim Chirkov
    Добавить, Поддержать, Вебмастеру