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 of communications device |
| char cChar | // character to transmit |
| ); |
Parameters
hFile
Identifies the communications device. The CreateFile function returns this handle.
cChar
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.
Character transmission is subject to normal flow control and handshaking. This function can only be called synchronously.
See Also