INF: Readpipe Return Codes

  - Microsoft SQL Server Programmer's Toolkit, version 4.2

SUMMARY

Two applications, Makepipe and Readpipe, are available to help diagnose problems creating and reading Named Pipes over the network. This article describes some of the more common return codes from the MS-DOS, OS/2, Windows and Windows NT versions of these applications.

MORE INFORMATION

Named Pipes provide an easy access conduit for reliable connection-oriented data transfer between two processes. These two processes are normally differentiated as a client process and a server process.

The server process (Makepipe) creates the pipe and manages access to it. The resources that make up the pipe are owned by the server process and physically exist on the station where the server process is running. The client process (Readpipe) uses the services of the underlying network protocols to access the remote pipe resources.

The server process (Makepipe) creates the named pipe and waits for a client to connect on the other end. The call to create the pipe (DosMakeNmPipe) returns a handle to the pipe. The client process (Readpipe) uses DosOpen and the name of the pipe to connect. Upon successful connection, DosOpen returns a handle to the pipe. Both sides can now use their respective handles to write to (DosWrite) and read from (DosRead) the pipe.

Both Makepipe (Server - OS/2, Windows NT), Readpipe (Client - OS/2, MS-DOS, Windows NT) and READPIPW.EXE (Client - Windows) are executable files used to determine if a Named Pipe Session from the Server is able to communicate with the Client on a supported network.

The following are the return codes that are commonly seen when encountering problems with Readpipe or the network:

STATUS     DESCRIPTION              POSSIBLE CAUSE

  3        Path Not Found           Named Pipes not installed correctly
  5        Access Denied            Permissions not granted on Named Pipes
  6        Invalid Handle           Network layer problem - check hardware
 13        Invalid Data             Wrong version of NETAPI.DLL
 53        Network Name Not Found   Network layer problem
 65        Network Access Denied    Permissions not granted on Named Pipes
 84        Out of Structures        Configuration settings
109        Broken Pipe              Network layer problem
110        Open Failed              Possible protocol incompatibility
206        Filename Exceeded Range  Server name more than eight characters
231        Pipe Busy                Pipe is not available

Windows NT Files:

The Windows NT files for MAKEPIPE.EXE and READPIPE.EXE are typically found in the C:\SQL\BINN directory. Both of these files must be executed within a Windows NT Command Prompt.

OS/2 Files:

The OS/2 files for MAKEPIPE.EXE and READPIPE.EXE are typically found in the C:\SQL\BINP directory. These programs are not Presentation Manager programs and as a result must be executed from within an OS/2 Window or OS/2 Full Screen session.

Windows Files:

A new version of Readpipe has been developed, called READPIPW.EXE. This is Win16 application that exists in the C:\SQL\BIN directory on the Windows workstation. An icon for this program is not automatically created when Microsoft SQL Administrator for Windows is installed. This program can be easily setup to run from the Windows Desktop via the Windows Program Manager.

MS-DOS Files:

The MS-DOS version of READPIPE.EXE is typically found in the C:\SQL\BIN directory. This program can be executed from a MS-DOS Command Prompt or from within a MS-DOS Prompt under Windows.

Two articles Q105104 "Readpipe for Windows Utility Tests Named Pipes" and Q68941 "Procedure for Testing Named Pipes" contain more information on the specific use of these programs.