fattach() — Attach a STREAMS-based file descriptor to a file in the file system name space

Standards

Standards / Extensions C or C++ Dependencies

XPG4.2
Single UNIX Specification, Version 3

 both  

Format

#define _XOPEN_SOURCE_EXTENDED 1
#include <stropts.h>

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

General description

The fattach() function attaches a STREAMS-based file descriptor to a file, effectively associating a path name with fildes. The fildes argument must be a valid open file descriptor associated with a STREAMS file. The path argument points to a path name 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() causes all path names 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 path names 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 before an fattach() call, continue to refer to the underlying file.

Returned value

If successful, fattach() returns 0.

If unsuccessful, fattach() returns -1 and sets errno to one of the following values.
Note: z/OS® UNIX services do not supply any STREAMS devices or pseudodevices. It is impossible for fattach() to attach a STREAMS-based file descriptor to a file. It will always return -1 with errno set to indicate the failure. See open() — Open a file for more information.
Error Code
Description
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.
EINVAL
The fildes argument does not refer to a STREAMS file.
ELOOP
Too many symbolic links were encountered in resolving path.
ENAMETOOLONG
The size of path exceeds PATH_MAX, or a component of path is longer than NAME_MAX, or path name resolution of a symbolic link produced an intermediate result whose length exceeds PATH_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 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.

Related information

Parent topic: Library functions