tn5250 for DOS (fwd)

[Michael Madore <mmadore@xxxxxxxxx>]

I send this again, because it may not have reached you:

Dear Mr. Madore,

first of all I want to thank you for creating tn5250. For some time I was searching for a 5250-emulation running under DOS. I found TN5250 via internet but unfortunately it was designed for UNIX. So I thought about porting it to MS-DOS. That should be possible, because you provided the source code, and it is written in C. Because there is no curses for DOS, I had to emulate the needed curses-functions. After resolving some minor Problems (e.g. the 12.51-version reached the 64k structure-limit of my borland 4.5 compiler) I was happy to get it running. I have to admit that I don’t make use of the environment-accommodation, it makes no sense under DOS anyway. If of some interest I can send you my curses-code. It is very simple and straightforward, but it works.

Now that I changed to the latest version (13.12) I couldn’t detect any more bugs except one: The dequeing of records in record.c works in the wrong direction: tn5250_record_list_add should return the first in the queue (list) instead of the last (record). This bug can lead to a blocking, if more than one telnet-record is sent in a TCP-block. It always did, when logging into a second AS400-session and getting the program-message screen. This problem didn’t occur under Linux. It seems that Linux uses an other blocking-algorithm than the DOS-TCP/IP-stack does (I use the one from FTP-Software).

Sincerely

Wolfram Koehn