Section: Linux Programmer's Manual (2)
lookup_dcookie - return a directory entry's path
int lookup_dcookie(u64 cookie, char *buffer, size_t len);
Look up the full path of the directory entry specified by the value
The cookie is an opaque identifier uniquely identifying a particular
The buffer given is filled in with the full path of the directory entry.
to return successfully,
the kernel must still hold a cookie reference to the directory entry.
returns the length of the path string copied into the buffer.
On error, -1 is returned, and
is set appropriately.
The buffer was not valid.
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.
The name could not fit in the buffer.
The kernel could not allocate memory for the temporary buffer holding
The process does not have the capability
required to look up cookie values.
The buffer was not large enough to hold the path of the directory entry.
Available since Linux 2.5.43.
error return was added in 2.5.70.
is a special-purpose system call, currently used only by the
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.
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