В man-е описана переменная окружения SCMXX_TTY, которая делает то же, что и ключ
-d. Раньше она действительно воспринималась. Сейчас -- нет. Проблема в
самодельной системе разбора параметров. Патч прилагается:
========8<=============================================
diff -ur scmxx-0.9.0/src/scmxx/scmxx_opt.c scmxx-0.9.0.new/src/scmxx/scmxx_opt.c
--- scmxx-0.9.0/src/scmxx/scmxx_opt.c   2006-02-06 21:00:19 +0300
+++ scmxx-0.9.0.new/src/scmxx/scmxx_opt.c       2006-06-05 19:17:30 +0400
@@ -214,10 +214,10 @@
 struct args_def args_list[] = {
   {"baud",'b',"SCMXX_BAUD",ARGS_PARAM_REQ,_("rate"),0,
    _("specify another than the compiled in baudrate")},
-  {"binary",'N',NULL,ARGS_PARAM_NONE,NULL,2,
-   _("binary file transfer")},
   {"device",'d',"SCMXX_TTY",ARGS_PARAM_REQ,_("device"),0,
    _("specify another than the compiled in device")},
+  {"binary",'N',NULL,ARGS_PARAM_NONE,NULL,2,
+   _("binary file transfer")},
   {"device-timeout",0,NULL,ARGS_PARAM_REQ,_("seconds"),0,
    _("return after this time if there is no answer")},
   {"dial",0,NULL,ARGS_PARAM_NONE,NULL,1,
========>8===================================================
Steps to Reproduce:
$ echo $SCMXX_TTY && scmxx --info
/dev/ttyS0
Using "KOI8-R" as system character set.
Accessing device /dev/ircomm1...done

$ echo $SCMXX_TTY && scmxx --info -d $SCMXX_TTY 
/dev/ttyS0
Using "KOI8-R" as system character set.
Accessing device /dev/ttyS0...done
OK, a modem device is present.

Actual Results:  
Accessing device /dev/ircomm1...done

Expected Results:  
Accessing device /dev/ttyS0...done