lookup_dcookie - return a directory entry's path
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.
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.
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 path.
The process does not have the capability CAP_SYS_ADMIN 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. The ENAMETOOLONG error return was added in 2.5.70.
lookup_dcookie() is Linux-specific.
This page is part of release 4.15 of the Linux
man-pages project. A description of the project, information about reporting bugs, and the latest version of this page, can be found at https://www.kernel.org/doc/man-pages/.