I looked at Cygwin a few weeks ago. I wasn't sure if it was a good idea to mix environments. Win32 people like to do things the Win32 way. It's even worse when you mix linux, dos, and NT all together. You end up with a confusing mishmash of ways to do things that no one can figure out. Even the makefiles confuse me sometimes, since I am not familiar with all of the command line switches that are used for things like rm. My first thought for the Win32 HowTo was to install Cygwin and then follow the Linux HowTo ;^)

Jeff.

Jeff Wormsley wrote

Remember if you do this for a Win32 machine, you won't be able to capture the output by piping to a file, as in "lazarus > debug.txt" because stderr does not get piped out like normal output.

That is why the Trace code supports alternate file output. If you set the TraceFileName variable with a file name then it outputs the data there and not to strerr or strout which ever one is used. Then you don't need to pipe to anything.

OK. I finally got the Trace working with Assert and it is committed. I changed all the gtkint.pp + incs., control.pp + .incs, forms.pp + incs., buttons.pp + incs.

I was testing with hello_world so I didn't hit some of the other files. They will have to be done as well. It is real simple to implement. Since just about every unit uses controls.pp I have added the utrace unit to controls.pp. It only needs to be added once.

+++++++++++++++++++++++++++++++++++++

+++ What needs to be added +++

At the beginning of the .pp file (not the inc's but the pp file that calls the inc's) add these lines

{$ifdef Trace}
   {$ASSERTIONS ON}
{$endif}

This is the switch that will turn Assertions on in the file. If you define Trace globally as in the make command:

make OPT=-dTrace

then every file that is compiled will turn this switch on and use Assertions. However, if you only want to do tracing in the file in which you are working. Just add the line:

{$ASSERTIONS ON}

somewhere at the top of your file and then only that file will output trace statements.

+++ What needs to be changed +++

Now for the Trace statements themselves. All you need is a standard Assert line with on caveat.

Assert(False, 'Trace:Your trace message');

Set the check to false so the Assert always gets fired. Then the very beginning of the message MUST START with "Trace:". This is a signal to the AssertErrorProc that this is just a trace statement and it just has to output the information. The only part of the message that does get output is the part AFTER the "Trace:" flag. The word "Trace:" does not get output.

So the above line on the console would be:

Your trace message

NOTE:
If you DO NOT put the "Trace:" flag at the beginning of the message the AssertErrorProc will ASSUME that this is a normal programming Assert call and will call the normal Handler which will output the message and raise an exception. This will allow normal use of the Assert as well as using it for tracing statements.

+++ Where does it output +++

The output itself defaults to the console. However it is possible to have the output go to a file of your choosing. To do this will required that you add the utrace unit to the file you are working with. Then someplace before the Trace statements that you want to see just set the following global variable:

TraceFileName := 'mylogfile';

where 'mylogfile' is of course any file of your choosing.

++++++++++++++++++++++++++++++++

For a simple example of how this works check the buttons.pp file and the buttonimp.inc file.

So now if you just type make to build your applications you don't get any output to the console. Do a "make OPT=-dTrace" and you will get a screen full of messages.

Remember if you do this for a Win32 machine, you won't be able to capture the output by piping to a file, as in "lazarus > debug.txt" because stderr does not get piped out like normal output.

Jeff.

You may want to change the default behaviour to output to stderr instead of output; this way you can split the 'normal' output from debug output. stderr is standard defined by FPC.

The reason it doesn't was to simplify coding. If you do an open with the filename '' {empty} it opens to stdout. This way I didn't need to really check the filename just open it and it would go to the correct place. I can of course fource the issue and go to strerr. I'll change it later today. :-)

You may want to change the default behaviour to output to stderr instead of output; this way you can split the 'normal' output from debug output. stderr is standard defined by FPC.

Just standard unix/linux behaviour.

Michael.

Hi

Hi

Or use 4dos, then you can do 'lazarus >& file'

Just use the 'redir' program that comes with djgpp, and then it should work fine.

Michael.