Implementation status: to be implemented

Synopsis

#include <stropts.h>

int fattach(int fildes, const char *path);

Description

The function attaches a STREAMS-based file descriptor to a file in the file system name space.

Arguments:

fildes - the file descriptor.
path - a pathname of an existing file.

The fattach() function attaches a STREAMS-based file descriptor to a file, effectively associating a pathname with fildes. The application ensures that the fildes argument is a valid open file descriptor associated with a STREAMS file. The path argument points to a pathname of an existing file. The application has appropriate privileges or is the owner of the file named by path and has write permission. A successful call to fattach causes all pathnames that name the file named by path to name the STREAMS file associated with fildes, until the STREAMS file is detached from the file. A STREAMS file can be attached to more than one file and can have several pathnames associated with it.

The attributes of the named STREAMS file are initialized as follows: the permissions, user ID, group ID, and times are set to those of the file named by path, the number of links is set to 1, and the size and device identifier are set to those of the STREAMS file associated with fildes. If any attributes of the named STREAMS file are subsequently changed (for example, by chmod()), neither the attributes of the underlying file nor the attributes of the STREAMS file to which fildes refers are affected.

File descriptors referring to the underlying file, opened prior to an fattach() call, continue to refer to the underlying file.

Return value

Upon successful completion, fattach() returns 0. Otherwise, -1 is returned and errno set to indicate the error.

Errors

[EACCES] Search permission is denied for a component of the path prefix, or the process is the owner of path but does not have write permissions on the file named by path.
[EBADF] The fildes argument is not a valid open file descriptor.
[EBUSY] The file named by path is currently a mount point or has a STREAMS file attached to it.
[ELOOP] A loop exists in symbolic links encountered during resolution of the path argument.
[ENAMETOOLONG] The length of a component of a pathname is longer than {NAME_MAX}.
[ENOENT] A component of path does not name an existing file or path is an empty string.
[ENOTDIR] A component of the path prefix names an existing file that is neither a directory nor a symbolic link to a directory, or the path argument contains at least one non- character and ends with one or more trailing characters.
[EPERM] The effective user ID of the process is not the owner of the file named by path and the process does not have appropriate privileges.

[EINVAL] The fildes argument does not refer to a STREAMS file.
[ELOOP] More than {SYMLOOP_MAX} symbolic links were encountered during resolution of the path argument.
[ENAMETOOLONG] The length of a pathname exceeds {PATH_MAX}, or pathname resolution of a symbolic link produced an intermediate result with a length that exceeds {PATH_MAX}.
[EXDEV] A link to a file on another file system was attempted.

Implementation tasks

  • Implement the stropts.h file
  • Implement fattach()