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mdoc(7) fixes.

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ru 2004-07-06 07:33:49 +00:00
parent 71acbf5699
commit ebd7b5c84f
1 changed files with 41 additions and 15 deletions
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56
share/man/man9/vn_fullpath.9
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@ -32,26 +32,32 @@
.Os
.Sh NAME
.Nm vn_fullpath
.Nd "Convert a vnode reference to a full pathname, given a process context"
.Nd "convert a vnode reference to a full pathname, given a process context"
.Sh SYNOPSIS
.In sys/param.h
.In sys/vnode.h
.Ft int
.Fn vn_fullpath "struct thread *td" "struct vnode *vp" "char **retbuf" "char **freebuf"
.Fo vn_fullpath
.Fa "struct thread *td" "struct vnode *vp" "char **retbuf" "char **freebuf"
.Fc
.Sh DESCRIPTION
The
.Fn
function makes a "best effort" attempt to generate a string pathname for
.Fn vn_fullpath
function makes a
.Dq "best effort"
attempt to generate a string pathname for
the passed (locked) vnode; the resulting path, if any, will be relative to
the root directory of the process associated with the passed thread pointer.
.Fn
The
.Fn vn_fullpath
function
is implemented by inspecting the VFS name cache, and attempting to
reconstruct a path from the process root to the object.
.Pp
This process is necessarily unreliable for several reasons: intermediate
entries in the path may not be found in the cache; files may have more
than one name (hard links), not all file systems use the name cache
(specifically, most synthetic file systems don't); a single name may
(specifically, most synthetic file systems do not); a single name may
be used for more than one file (in the context of file systems covering
other file systems); a file may have no name (if deleted but still
open or referenced).
@ -61,7 +67,7 @@ Code consuming the results of this function should anticipate (and
properly handle) failure.
.Pp
Its arguments are:
.Bl -tag -width freebuf
.Bl -tag -width ".Fa freebuf"
.It Fa td
The thread performing the call; this pointer will be dereferenced to find
the process and its file descriptor structure, in order to identify the
@ -69,23 +75,43 @@ root vnode to use.
.It Fa vp
The vnode to search for; must be locked by the caller.
.It Fa retbuf
Pointer to a char * that vn_fullpath may (on success) point at a newly
Pointer to a
.Vt "char *"
that
.Fn vn_fullpath
may (on success) point at a newly
allocated buffer containing the resulting pathname.
.It Fa freebuf
Pointer to a char * that vn_fullpath may (on success) point at a buffer
Pointer to a
.Vt "char *"
that
.Fn vn_fullpath
may (on success) point at a buffer
to be freed, when the caller is done with
.Fa retbuf .
.El
.Pp
Typical consumers will declare two character pointers: fullpath and
freepath; they will set freepath to
Typical consumers will declare two character pointers:
.Va fullpath
and
.Va freepath ;
they will set
.Va freepath
to
.Dv NULL ,
and fullpath to a name to use
and
.Va fullpath
to a name to use
in the event that the call to
.Fn
.Fn vn_fullpath
fails.
After done with the value of fullpath, the caller will check if freepath
is non-NULL, and if so, invoke
After done with the value of
.Va fullpath ,
the caller will check if
.Va freepath
is
.Pf non- Dv NULL ,
and if so, invoke
.Xr free 9
with a pool type of
.Dv M_TEMP .