DosTransactNmPipe
From EDM2
This call performs a write followed by a read on a duplex message pipe.
Syntax
DosTransactNmPipe (Handle, InBuffer, InBufferLen, OutBuffer, OutBufferLen, BytesOut)
Parameters
- Handle (HPIPE) - input
- Named pipe handle returned by DosMakeNmPipe or DosOpen.
- InBuffer (PBYTE) - input
- Address of the buffer to write to the pipe.
- InBufferLen (USHORT) - input
- Number of bytes to be written.
- OutBuffer (PBYTE) - output
- Address of the buffer for returned data.
- OutBufferLen (USHORT) - input
- Maximum size, number of bytes, of returned data.
- BytesOut (PUSHORT) - output
- Address of the number of bytes read.
Return Code
- rc (USHORT) - return
- Return code descriptions are:
- 0 NO_ERROR
- 11 ERROR_BAD_FORMAT
- 230 ERROR_BAD_PIPE
- 231 ERROR_PIPE_BUSY
- 233 ERROR_PIPE_NOT_CONNECTED
- 234 ERROR_MORE_DATA
Remarks
DosTransactNmPipe is intended for use only on duplex message pipes. If this call is issued and the pipe is not a duplex message pipe, ERROR_BAD_FORMAT is returned.
This call enables you to implement transaction-oriented dialogs. DosTransactNmPipe writes the entire InBuffer to the pipe and then reads a response from the pipe into the OutBuffer. The current state of blocking/non-blocking has no effect. DosTransactNmPipe does not return until a message has been read into the OutBuffer. If the OutBuffer is too small to contain the response message, ERROR_MORE_DATA is returned, as described for DosRead.
Binding
C
#define INCL_DOSNMPIPES USHORT rc = DosTransactNmPipe(Handle, InBuffer, InBufferLen, OutBuffer, OutBufferLen, BytesOut); HPIPE Handle; /* Pipe handle */ PBYTE InBuffer; /* Write buffer */ USHORT InBufferLen; /* Write buffer length */ PBYTE OutBuffer; /* Read buffer (returned) */ USHORT OutBufferLen; /* Read buffer length */ PUSHORT BytesOut; /* Bytes read (returned) */ USHORT rc; /* return code */
MASM
EXTRN DosTransactNmPipe:FAR INCL_DOSNMPIPES EQU 1 PUSH WORD Handle ;Pipe handle PUSH@ OTHER InBuffer ;Write buffer PUSH WORD InBufferLen ;Write buffer length PUSH@ OTHER OutBuffer ;Read buffer (returned) PUSH WORD OutBufferLen ;Read buffer length PUSH@ WORD BytesOut ;Bytes read (returned) CALL DosTransactNmPipe Returns WORD