The fdetach() function detaches a STREAMS-based file from the file to which it was attached by a previous call to fattach(3C). The path argument points to the pathname of the attached STREAMS file. The process must have appropriate privileges or be the owner of the file. A successful call to fdetach() causes all pathnames that named the attached STREAMS file to again name the file to which the STREAMS file was attached. All subsequent operations on path will operate on the underlying file and not on the STREAMS file.

All open file descriptions established while the STREAMS file was attached to the file referenced by path, will still refer to the STREAMS file after the fdetach() has taken effect.

If there are no open file descriptors or other references to the STREAMS file, then a successful call to fdetach() has the same effect as performing the last close(2) on the attached file.

Upon successful completion, fdetach() returns 0. Otherwise, it returns -1 and sets errno to indicate the error.

The fdetach() function will fail if:

EACCES

Search permission is denied on a component of the path prefix.

EPERM

The effective user ID is not the owner of path and the process does not have appropriate privileges.

ENOTDIR

A component of the path prefix is not a directory.

ENOENT

A component of path does not name an existing file or path is an empty string.

EINVAL

The path argument names a file that is not currently attached.

ENAMETOOLONG

The size of a pathname exceeds PATH_MAX, or a pathname component is longer than NAME_MAX while _POSIX_NO_TRUNC is in effect.

ELOOP

Too many symbolic links were encountered in resolving path.

The fdetach() function may fail if:

ENAMETOOLONG

Pathname resolution of a symbolic link produced an intermediate result whose length exceeds PATH_MAX.

fdetach(1M), close(2), fattach(3C), streamio(7I)

STREAMS Programming Guide