APIChecker tests, if values passed to OS-functions are valid.

This version only checks some exec.library functions and writes
errors to the serial port.

My patch.library (available on Aminet:util/libs/PatchLib.lha) is
used to patch the OS-functions.

As I don't expect to resume work on this project in the near future
(last changes were done almost a year ago) I decided to release
the source to public domain.

So anyone is free to pick up this project, as long as my name is
mentioned somewhere in the documentation.

 PERMSSN    UID  GID    PACKED    SIZE  RATIO     CRC       STAMP          NAME
---------- ----------- ------- ------- ------ ---------- ------------ -------------
[generic]                 5724   15468  37.0% -lh5- 6b01 Mar  9  1996 apichecker/APIChecker
[generic]                10078   50863  19.8% -lh5- 9d07 Feb  9  1997 apichecker/APIChecker.asm
[generic]                  383     656  58.4% -lh5- 137d Feb  9  1997 apichecker/APIChecker.readme
[generic]                  829    2811  29.5% -lh5- ab19 Sep 17  1995 apichecker/ASMMacros.i
[generic]                 6625   11608  57.1% -lh5- e984 Jan 28  1997 apichecker/libs/patch.library
[generic]                 2832    8703  32.5% -lh5- a98a Jan 29  1997 apichecker/patchtags.i
---------- ----------- ------- ------- ------ ---------- ------------ -------------
 Total         6 files   26471   90109  29.4%            Feb 11  1997