From: Eric Hodel <drbrain@...7.net>
Date: 2011-01-25T03:58:23+09:00
Subject: Re: FileUtils writing to stderr

On Jan 24, 2011, at 09:32, Eric Hodel wrote:
> On Jan 24, 2011, at 5:25, "Mark L." <marcuslamb@yahoo.com> wrote:
>> Hi there,
>> 
>> I'm having a few issues with FileUtils writing stuff to stderr when no error has occurred. For example I might have the following simple
>> Rakefile:
>> 
>> require 'rake'
>> task :clean do
>> rm_rf 'test'
>> end
> 
> Note that rake's rm_rf is not exactly FileUtils' rm_rf
> 
>> When I run
>> 
>> rake clean 2> err
>> 
>> In the err file I see:
>> 
>> 'rm -rf test'
>> 
>> I would expect this to be sent to stdout rather than err.
> 
> Why? I expect informational messages on stderr. This way rake's messages don't interfere with a rake user's output. By having rake's messages on stderr a rake task author can write tasks that can be piped to other commands.
> 
> rake email | sendmail # for example
> 
> (Yes, rake currently outputs a message on stdout. I have fixed that in trunk.)
> 
>> The problem that I have is that I am trying to detect a rake failure from within ant. Rake doesn't seem to return the correct error code so I was testing for failure by detecting if anything was written to stderr.
> 
> You should query $?, not stderr. Rake should be behaving like a standard unix command. 
> 
>> My ant task would thus look something like this:
>> 
>> <target name="rake">
>> <exec executable="rake" failonerror="true" errorproperty="rake.err">
>>   <arg value="clean">
>> </exec>
>> <fail if="rake.err" message="Rake failed with: ${rake.err}"/>
>> </target>
>> 
>> This works fine except when I try to use the FileUtils methods. rm_rf causes it to fail as does mkdir_p.
>> 
>> Any suggestions?
> 
> AFAIK rm -rf and mkdir -p always exit 0.

My mistake, these can exit 1.

I suppose the question then is "what does rm -f mean for rake's exit status?"

If I'm writing a clean task that uses rm -f I suppose I'm saying it's OK for clean to not delete some things.

> What is your rake task that exits 0 improperly?