WaitNamedPipe info  Overview  Group

The WaitNamedPipe function waits until either a time-out interval elapses or an instance of the specified named pipe is available to be connected to (that is, the pipe’s server process has a pending ConnectNamedPipe operation on the pipe).

BOOL WaitNamedPipe(

LPCTSTR lpNamedPipeName,	// address of name of pipe to wait for
DWORD nTimeOut	// time-out interval, in milliseconds
);

Parameters

lpNamedPipeName

Points to a null-terminated string that specifies the name of the named pipe. The string must include the name of the computer on which the server process is executing. A period may be used for the servername if the pipe is local. The following pipe name format is used:

\\servername\pipe\pipename

nTimeOut

Specifies the number of milliseconds that the function will wait for an instance of the named pipe to be available. One of the following values can be used instead of specifying a number of milliseconds:

Value	Meaning
NMPWAIT_USE_DEFAULT_WAIT	The time-out interval is the default value specified by the server process in the CreateNamedPipe function.
NMPWAIT_WAIT_FOREVER	The function does not return until an instance of the named pipe is available.

Return Values

If an instance of the pipe is available before the time-out interval elapses, the return value is nonzero.

If an instance of the pipe is not available before the time-out interval elapses, the return value is zero. To get extended error information, call GetLastError.

Remarks

If no instances of the specified named pipe exist, the WaitNamedPipe function returns immediately, regardless of the time-out value.

If the function succeeds, the process should use the CreateFile function to open a handle to the named pipe. A return value of TRUE indicates that there is at least one instance of the pipe available. A subsequent CreateFile call to the pipe can fail, because the instance was closed by the server or opened by another client.

See Also

CallNamedPipe, ConnectNamedPipe, CreateFile, CreateNamedPipe