On 2020-02-28 20:23, Corinna Vinschen wrote:
- Is it a safe bet that ClearCommError returns valid values in st.cbInQue even if one of the error conditions occur? Maybe the right thing to do is to return 0 in certain error cases...?
The win32 api documentation does not mention anything about not returning proper device status as long as the function succeeds...
Anyhow in my pursuit for the truth I whipped up a small test program and strace:d it (with some extra debug printout in fhandler_serial::ioctl)
127 2403456 [main] python2.7 1662 fhandler_serial::ioctl: 0 = ioctl(541B, 0xFFFFBCB0) ev=C st.cbInQue=7 216 3406481 [main] python2.7 1662 fhandler_serial::ioctl: 0 = ioctl(541B, 0xFFFFBCB0) ev=C st.cbInQue=E 90 4409676 [main] python2.7 1662 fhandler_serial::ioctl: 0 = ioctl(541B, 0xFFFFBCB0) ev=C st.cbInQue=15 141 5413027 [main] python2.7 1662 fhandler_serial::ioctl: 0 = ioctl(541B, 0xFFFFBCB0) ev=C st.cbInQue=1C 129 6416204 [main] python2.7 1662 fhandler_serial::ioctl: 0 = ioctl(541B, 0xFFFFBCB0) ev=C st.cbInQue=23 121 7419254 [main] python2.7 1662 fhandler_serial::ioctl: 0 = ioctl(541B, 0xFFFFBCB0) ev=C st.cbInQue=2A 203 8423829 [main] python2.7 1662 fhandler_serial::ioctl: 0 = ioctl(541B, 0xFFFFBCB0) ev=C st.cbInQue=31 89 9427183 [main] python2.7 1662 fhandler_serial::ioctl: 0 = ioctl(541B, 0xFFFFBCB0) ev=C st.cbInQue=38 131 10431271 [main] python2.7 1662 fhandler_serial::ioctl: 0 = ioctl(541B, 0xFFFFBCB0) ev=C st.cbInQue=3F 118 11435254 [main] python2.7 1662 fhandler_serial::ioctl: 0 = ioctl(541B, 0xFFFFBCB0) ev=C st.cbInQue=46
- Did you actually try if this fixes your problem? It's pretty simple to build the Cygwin DLL https://cygwin.com/faq.html#faq.programming.building-cygwin
I patched it yesterday and it solved the problem... /Ake -- Problem reports: http://cygwin.com/problems.html FAQ: http://cygwin.com/faq/ Documentation: http://cygwin.com/docs.html Unsubscribe info: http://cygwin.com/ml/#unsubscribe-simple
