My poor man CW interface

When I got involved in ham radio I was soon fascinated by CW, so I learnt Morse code and started making contacts. A few days ago I participated as a station in an award and decided to try out working some station in CW instead of my usual SSB operation. I soon got tired of sending CQ and reports by hand so I started thinking of making a CW interface with what I had at the moment. The logging program I use is CQRLOG under Ubuntu 16.04.
Because I did not want to risk burning my rig I decided to use the interface I usually work digital modes with because it was insulated. This is basically a couple of insulation transformers for audio in/out and an optocoupler for the PTT signal. The latter is keyed via RTS of an RS-232 port connected to the USB of my laptop trough a converter. What I did was simply to connect the PTT of the interface to the KEY port of my FT 817. Now the software part: modulating CW trough RTS and not TX as usually done. After a bit of searching I found that cwdaemon with a simple code trick did the job. This idea was found in a blog I am not able to find again.
I simply downloaded the source, went into the src folder and opened the ttys.c file. All I had to do was to swap:

int ttys_ptt

with

int ttys_cw

and vice versa, in this way the program will key the PTT instead of the TX pin. Then I simply ran the usual ./configure, make, make install and then 
cwdaemon -s 20 -d ttyUSB0 -n -x n
Hope this post helps someone needing a CW interface in a hurry,
73s de Luca IU3IDF

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