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.\" Copyright (c) 1996 Doug Rabson
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.Dd July 24, 1996
.Os
.Dt VOP_BLKATOFF 9
.Sh NAME
.Nm VOP_BLKATOFF
.Nd return a filesystem buffer for part of a file
.Sh SYNOPSIS
.Fd #include <sys/vnode.h>
.Fd #include <sys/buf.h>
.Ft int
.Fn VOP_BLKATOFF "struct vnode *vp" "off_t offset" "char **res" "struct buf **bpp"
.Sh DESCRIPTION
.Pp
The arguments are:
.Bl -tag -width offset
.It Ar vp
The vnode representing the file.
.It Ar offset
The byte offset into the file where the buffer should start.
.It Ar res
Return parameter for a pointer to the last valid byte in the buffer.
.It Ar bpp
Return parameter for the buffer.
.El
.Pp
Return buffer with the contents of block
.Fa offset
from the beginning of file
.Fa ip .
.Fa res
is non-zero, fill it in with a pointer to the
remaining space in the directory.
.Pp
This call is only used internally by the UFS filesystem.
.Sh RETURN VALUES
Zero is returned on success, otherwise an error is returned.
.Sh SEE ALSO
.Xr vnode 9 ,
.Xr buf 9
.Sh AUTHORS
This man page was written by Doug Rabson.