TransmitCommChar

The TransmitCommChar function transmits a specified character ahead of any pending data in the output buffer of the specified communications device.

BOOL TransmitCommChar(
  HANDLE hFile,  // handle to communications device
  char cChar     // character to transmit
);

Parameters

hFile

[in] Handle to the communications device. The CreateFile function returns this handle.

cChar

[in] Specifies the character to be transmitted.

Return Values

If the function succeeds, the return value is nonzero.

If the function fails, the return value is zero. To get extended error information, call GetLastError.

Remarks

The TransmitCommChar function is useful for sending an interrupt character (such as a CTRL+C) to a host system.

If the device is not transmitting, TransmitCommChar cannot be called repeatedly. Once TransmitCommChar places a character in the output buffer, the character must be transmitted before the function can be called again. If the previous character has not yet been sent, TransmitCommChar returns an error.

Requirements

  Windows NT/2000: Requires Windows NT 3.1 or later.
  Windows 95/98: Requires Windows 95 or later.
  Header: Declared in Winbase.h; include Windows.h.
  Library: Use Kernel32.lib.

See Also

Communications Overview, Communication Functions, CreateFile, WaitCommEvent