PRB: Named Pipe Write() Limited to 64K

ID: Q119218

The information in this article applies to:

Microsoft Win32 Application Programming Interface (API), included with:
- Microsoft Windows NT, versions 3.1, 3.5, 3.51, 4.0

SYMPTOMS

WriteFile() returns FALSE and GetLastError() returns

ERROR_MORE_DATA

when WriteFile() writes to a message-mode named pipe using a buffer greater than 64K.

CAUSE

There is a 64K limit on named pipe writes.

RESOLUTION

The error is different from ERROR_MORE_DATA on the reader side, where bytes have already been read and the operation should be retried for the remaining message. The real error is STATUS_BUFFER_OVERFLOW. No data is transmitted; therefore, the write operation must be retried using a smaller buffer.

Additional query words:

Keywords : kbnetwork kbAPI kbIPC kbKernBase kbPipes kbSDKPlatform kbGrpNet kbGrpKernBase
Version : winnt:3.1,3.5,3.51,4.0
Platform : winnt
Issue type :