search for: select_read

..., I tried using 2.6.1 version for windows with a Megatec-compatible UPS and was surprised to find out it doesn't work at all. The reason for that is blazer_ser using ser_get_buf specifying a buffer large enough to accept any reasonably possible response, setting buflen accordingly. That calls select_read() and it's supposed to wait until something is available and then to read up all the data from port, returning the number of bytes read. But the windows version apparently differs, the way it's currently implemented it either reads up to buflen bytes or returns an error indicating a timeout...

...elect_stuff::poll: returning 0 14:04:19 [main] rsync 2472 select_stuff::cleanup: calling cleanup routines 14:04:19 [main] rsync 2472 select_stuff::~select_stuff: deleting select records 14:04:19 [main] rsync 2472 cygwin_select: 5, 0x22E9C8, 0x22E9D0, 0x0, 0x22E9C0 14:04:19 [main] rsync 2472 dtable::select_read: fd 3 14:04:19 [main] rsync 2472 dtable::select_write: fd 4 14:04:19 [main] rsync 2472 cygwin_select: to->tv_sec 60, to->tv_usec 0, ms 60000 14:04:19 [main] rsync 2472 cygwin_select: sel.always_ready 0 14:04:19 [main] rsync 2472 start_thread_socket: Handle 0x308 14:04:19 [main] rsync 2472 s...

...plies on slow systems. > > The ser_get_line() function is unreliable when reading multi-line > replies from the UPS. See > docs/new-drivers.txt for an explanation why. Basically this will > only work if the driver is able > to keep up with the flow of data from the UPS and the select_read() > function in ser_get_line() > reads one character at a time. In that case, switching to > ser_get_char() is more reliable, > since that is not prone to losing data after reading ENDCHAR. What was I thinking? I completely missed the fact that the UPScode II driver sets the comm...

In order to improve the diagnostics for serial connected devices, I would like to add the possibility to differentiate between errors and timeouts. For the ser_get_char() and ser_get_buf_len() we might do this by changing the return value. For the first, return value -1 would be an error, 0 a timeout and 1 success. The latter could return -1 on error, between 0 and (buflen-1) for a