dfs_sopen

Opens the requested file in Direct File Mode.

Library:LibC
Classification:Novell
Service:Direct File System

Syntax

  #include <dfs.h>  
   
  int dfs_sopen (
     const char   *path,
     int           oflag,
     int           shflag,
     int          *err,
     ... );

Parameters

path

(IN) Points to the name of the file to be opened. The file name must be NULL-terminated and must include the path including the volume name but not the server name.

oflag

(IN) Specifies the open access mode. See File Control Open Modes.

shflag

(IN) Specifies the share mode for the file and uses one of the following:

Flag

Value

Description

SH_DENYRW

0x00000010

Deny read and write mode

SH_DENYWR

0x00000020

Deny write mode

SH_DENYRD

0x00000030

Deny read mode

SH_DENYNO

0x00000040

Deny none mode, which allows read and write access to the file
err

(OUT) Points to an error code value, when dfs_sopen returns -1.

...

(IN) Specifies an optional mode argument when the O_CREAT flag is specified in oflag. See File Access Modes and NetWare Attributes.

Return Values

If successful, returns a file descriptor, which is a non-negative integer. Otherwise, returns -1 and sets the err parameter to one of the following values:

Decimal

Constant

Description

1

ENONENT

No such file. O_CREAT is not set and the named file does not exist; or O_CREAT is set and either the path prefix does not exist or the path argument points to an empty string.

4

EBADF

Invalid path.

5

ENOMEM

The system is unable to allocate resources.

6

EACCES

Permission denied.

7

EEXIST

The named file exists and O_CREAT and O_EXCL are set.

9

EINVAL

Invalid parameter.

10

ENFILE

The maximum allowable number of files is currently open in the system.

11

EMFILE

The maximum number of files are currently open.

12

ENOSPC

There is no space left on the device to create the file.

25

ENXIO

The device does not exist.

28

EIO

A physical I/O error occurred.

63

EINTR

A signal was caught during the execution of the function.

64

EISDIR

The specified file is a directory and oflag includes O_WRONLY or O_RDWR.

65

ENAMETOOLONG

The length of the path parameter exceeds the maximum allowed length, or a component of the path parameter is longer than the maximum name length.

67

ENOTDIR

A component specified in the path parameter is not a directory.

76

EROFS

The named file resides on a read-only file system.

79

ENOTSUP

The NLM is loaded in protected address space. This operation is supported only in kernel address space.

81

EOVERFLOW

The operation would overflow.

106

ENOCONTEXT

The current thread has not context.

Remarks

The name of the file to be opened is given by the path parameter. The file is opened according to the mode specified by the oflag parameter.

When a file is opened in direct file mode by calling dfs_sopen, DFS flags the file as being in direct file mode. In this mode, the cache is bypassed for future I/O calls to the file. Existing cache entries for the file are flushed and a turbo FAT for the file is built if one does not currently exist.

This function can cause problems with other applications that have already opened the file in normal non-direct mode. In this case, the file is switched to direct mode, and the program with the file open in normal mode is able to read the file but cannot write to it. A close must be issued for each handle obtained by an open for the file before the file can be reopened for full normal mode access again (see Input and Output).

See Also