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LFS_MARKV(2)		       System Calls Manual		    LFS_MARKV(2)

NAME
     lfs_markv -- rewrite disk blocks to new disk locations

LIBRARY
     Standard C Library (libc, -lc)

SYNOPSIS
     #include <sys/types.h>
     #include <ufs/lfs/lfs.h>

     int
     lfs_markv(fsid_t *fsidp, BLOCK_INFO *blkiov, int blkcnt);

DESCRIPTION
     lfs_markv()  rewrites the blocks specified in blkiov to new disk locations,
     for the purposes of grouping them next to one another, or to move them  out
     of  a  segment to clean it.  All fields of the BLOCK_INFO structure must be
     filled in, except for bi_segcreate.  If bi_daddr is not the correct current
     address for logical block bi_lbn of the file with inode number bi_inode, or
     if the file's version number does not match bi_version, the block will  not
     be written to disk, but no error will be returned.

     The  fsidp  argument  contains the id of the filesystem to which the inodes
     and blocks belong.  The bi_bp field contains bi_size bytes of  data  to  be
     written  into  the  appropriate  block.   If bi_lbn is specified as LFS_UN-
     USED_LBN, the inode itself will be rewritten.

     The blkiov argument is an array of BLOCK_INFO structures (see below).   The
     blkcnt argument determines the size of the blkiov array.

     typedef struct block_info {
	 ino_t	     bi_inode;	   /* inode # */
	 ufs_daddr_t bi_lbn;	   /* logical block w/in file */
	 ufs_daddr_t bi_daddr;	   /* disk address of block */
	 time_t      bi_segcreate; /* origin segment create time */
	 int	     bi_version;   /* file version number */
	 void	    *bi_bp;	   /* data buffer */
	 int	     bi_size;	   /* size of the block (if fragment) */
     } BLOCK_INFO;

RETURN VALUES
     lfs_markv() returns 0 on success, or -1 on error.

ERRORS
     An error return from lfs_markv() indicates:

     [EFAULT]		fsidp  points  outside	the  process's allocated address
			space.

     [EINVAL]		*fsidp does not specify a valid filesystem.

     [EBUSY]		One or more of the inodes whose blocks were to be  writ-
			ten was locked, and its blocks were not rewritten.

SEE ALSO
     lfs_segclean(2), lfs_segwait(2), lfs_cleanerd(8)

HISTORY
     The lfs_markv() function call appeared in 4.4BSD.

BUGS
     The  functionality  of  lfs_markv()  does	not really belong in user space.
     Among other things it could be used to work  around  the  SF_IMMUTABLE  and
     SF_APPEND file flags (see chflags(2)).

NetBSD 5.0			  May 23, 2000			    LFS_MARKV(2)
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