Technical Reference: Base Operating System and Extensions, Volume 1

fattach Subroutine

Purpose

Attaches a STREAMS-based file descriptor to a file.

Syntax

#include <stropts.h>
int fattach(int fildes, const char *path);

The fattach subroutine attaches a STREAMS-based file descriptor to a file, effectively associating a pathname with fildes. The fildes argument must be a valid open file descriptor associated with a STREAMS file. The path argument points to a pathname of an existing file. The process must have appropriate privileges, or must be the owner of the file named by path and have write permission. A successful call to fattach subroutine causes all pathnames that name the file named by path to name the STREAMS file associated with fildes, until the STEAMS 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 subroutine), 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 subroutine, continue to refer to the underlying file.

Parameters

fildes	A file descriptor identifying an open STREAMS-based object.
path	An existing pathname which will be associated with fildes.

Return Value

0	Successful completion.
-1	Not successful and errno set to one of the following.

Errno Value

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 permission on the file named by path.
EBADF	The file referred to by fildes is not an open file descriptor.
ENOENT	A component of path does not name an existing file or path is an empty string.
ENOTDIR	A component of the path prefix is not a directory.
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 privilege.
EBUSY	The file named by path is currently a mount point or has a STREAMS file attached to it.
ENAMETOOLONG	The size of path exceeds {PATH_MAX}, or a component of path is longer than {NAME_MAX}.
ELOOP	Too many symbolic links wer encountered in resolving path.
EINVAL	The fildes argument does not refer to a STREAMS file.
ENOMEM	Insufficient storage space is available.

Implementation Specifics

These subroutines are part of Base Operating System (BOS) Runtime.

Related Specifics

The fdetach (fdetach Subroutine) subroutine, isastream subroutine.