On Mon, 8 Jun 2020, Christo Crause via fpc-devel wrote:
Michael, it is entirely possible that I am misunderstanding your suggestion, I probably don't grasp the complexities of the RTL texmode IO system and also not explaining my intention clearly, for this I apologise. Take for example the esp32 unit provided by Florian, here the link between the underlying OS output and the RTL is configured by calling OpenIO and providing readchar and writechar functions which in turn calls getchar and putchar ( https://github.com/ccrause/freepascal/blob/76911c528251b48e18c348de1758c098ee9fb763/rtl/freertos/xtensa/esp32.pp#L106). In this unit Florian uses a custom printpchar procedure which pushes characters to the OS and at the end directly calls the OS fflush function. This ensures that the haltproc message gets transmitted before the cpu goes to sleep. I'm trying to change the controller unit to use standard RTL write functionality, since this gets configured during unit initialization anyway. My attempt at "Pascalizing" Florian's version ( https://github.com/ccrause/freepascal/blob/76911c528251b48e18c348de1758c098ee9fb763/rtl/freertos/xtensa/esp8266.pp#L59) calls the normal write functionality and works, except for the last string before esp_deep_sleep which doesn't reach the remote terminal. At the moment I fix this by directly calling the OS fflush function. The only configuration option exposed via consoleio is OpenIO, which doesn't have a parameter for a low level flush function. I could create an overloaded OpenIO function with an extra parameter for a flush function pointer, and call this, if assigned, at the end of Console_Write. Is this kind of the lower level detail behind your suggestion Michael?
I would add a flushfunc to TUserData and to the OpenIO call in consoleIO: Type TFlushIOFunc = function(UserData: pointer): boolean; and change PUserData = ^TUserData; TUserData = record WriteChar: TWriteCharFunc; ReadChar: TReadCharFunc; FlushFunc : TFlushIOFunc; UserData: Pointer; end; change procedure OpenIO(var f: Text; AWrite: TWriteCharFunc; ARead: TReadCharFunc; AMode: word; AUserData: pointer); to procedure OpenIO(var f: Text; AWrite: TWriteCharFunc; ARead: TReadCharFunc; aFlush : TFlushIOFunc; AMode: word; AUserData: pointer); and add userdata^.FlushFunc := AFlush; At the end of Console_Write I would call this new flush function: if i<>t.BufPos then InOutRes:=101 else begin if userdata^.FlushFunc(userdata^.UserData) then InOutRes:=0 else InOutRes:=101; end; t.BufPos:=0; end; Console_Write is only called when the internal buffer is full or when the output must be forced to terminal, so that should be sufficient. Hope this helps, Michael. _______________________________________________ fpc-devel maillist - fpc-devel@lists.freepascal.org https://lists.freepascal.org/cgi-bin/mailman/listinfo/fpc-devel