lookup_dcookie(2) -- Linux man page
NAME
lookup_dcookie - return a directory entry's path
SYNOPSIS
int lookup_dcookie(u64 cookie, char * buffer, size_t len);
DESCRIPTION
Look up the full path of the directory entry specified by the value
cookie
The cookie is an opaque identifier uniquely identifying a particular directory
entry. The buffer given is filled in with the full path of the directory
entry.
For
lookup_dcookie
to return successfully,
the kernel must still hold a cookie reference to the directory entry.
NOTES
lookup_dcookie
is a special-purpose system call, currently used only by the oprofile profiler.
It relies on a kernel driver to register cookies for directory entries.
The path returned may be suffixed by the string " (deleted)" if the directory
entry has been removed.
RETURN VALUE
On success,
lookup_dcookie
returns the length of the path string copied into the buffer.
On error, -1 is returned, and
errno
is set appropriately.
ERRORS
EPERM
The process does not have the capability to look up cookie values.
- EINVAL
-
The kernel has no registered cookie/directory entry mappings at the
time of lookup, or the cookie does not refer to a valid directory entry.
- ENOMEM
-
The kernel could not allocate memory for the temporary buffer holding
the path.
- ERANGE
-
The buffer was not large enough to hold the path of the directory entry.
- ENAMETOOLONG
-
The name could not fit in the buffer.
- EFAULT
-
The buffer was not valid.
CONFORMING TO
lookup_dcookie
is Linux-specific.
AVAILABILITY
Since Linux 2.5.43.
The ENAMETOOLONG error return was added in 2.5.70.
|
