Redirect stderr to sys.stdout for build output.

Redirect stderr to sys.stdout for build output.

The stderr is currently not being displayed on the buildbot.
Committed: https://code.google.com/p/dart/source/detail?r=13932

[Mads Ager (google), 2012-10-23 08:33:04]

lgtm

[Mads Ager (google), 2012-10-23 08:34:15]

https://codereview.chromium.org/11228050/diff/1/tools/build.py
File tools/build.py (right):

https://codereview.chromium.org/11228050/diff/1/tools/build.py#newcode321
tools/build.py:321: process = subprocess.Popen(args, stderr=sys.stdout)
Should this just be stderr=STDOUT?

[ahe, 2012-10-23 08:36:51]

LGTM!

https://codereview.chromium.org/11228050/diff/1/tools/build.py
File tools/build.py (right):

https://codereview.chromium.org/11228050/diff/1/tools/build.py#newcode321
tools/build.py:321: process = subprocess.Popen(args, stderr=sys.stdout)
On 2012/10/23 08:34:15, Mads Ager wrote:
> Should this just be stderr=STDOUT?

That would be stderr=subprocess.STDOUT but that doesn't work.

[Ivan Posva, 2012-10-23 16:06:06]

Thanks!

LGTM
-Ivan

[Emily Fortuna, 2012-10-23 16:46:16]

https://codereview.chromium.org/11228050/diff/1/tools/build.py
File tools/build.py (right):

https://codereview.chromium.org/11228050/diff/1/tools/build.py#newcode321
tools/build.py:321: process = subprocess.Popen(args, stderr=sys.stdout)
On 2012/10/23 08:36:51, ahe wrote:
> On 2012/10/23 08:34:15, Mads Ager wrote:
> > Should this just be stderr=STDOUT?
> 
> That would be stderr=subprocess.STDOUT but that doesn't work.

Why does stderr=subprocess.STDOUT not work?

[ahe, 2012-10-29 12:59:38]

https://codereview.chromium.org/11228050/diff/1/tools/build.py
File tools/build.py (right):

https://codereview.chromium.org/11228050/diff/1/tools/build.py#newcode321
tools/build.py:321: process = subprocess.Popen(args, stderr=sys.stdout)
On 2012/10/23 16:46:17, Emily Fortuna wrote:
> On 2012/10/23 08:36:51, ahe wrote:
> > On 2012/10/23 08:34:15, Mads Ager wrote:
> > > Should this just be stderr=STDOUT?
> > 
> > That would be stderr=subprocess.STDOUT but that doesn't work.
> 
> Why does stderr=subprocess.STDOUT not work?

I don't know. We tried and it didn't work. However, it turned out that this
didn't work either.

[Emily Fortuna, 2012-10-29 16:17:56]

https://codereview.chromium.org/11228050/diff/1/tools/build.py
File tools/build.py (right):

https://codereview.chromium.org/11228050/diff/1/tools/build.py#newcode321
tools/build.py:321: process = subprocess.Popen(args, stderr=sys.stdout)
On 2012/10/29 12:59:39, ahe wrote:
> On 2012/10/23 16:46:17, Emily Fortuna wrote:
> > On 2012/10/23 08:36:51, ahe wrote:
> > > On 2012/10/23 08:34:15, Mads Ager wrote:
> > > > Should this just be stderr=STDOUT?
> > > 
> > > That would be stderr=subprocess.STDOUT but that doesn't work.
> > 
> > Why does stderr=subprocess.STDOUT not work?
> 
> I don't know. We tried and it didn't work. However, it turned out that this
> didn't work either.

alternatively:
process = subprocess.Popen(args, stderr=subprocess.PIPE, stdout=subprocess.PIPE)
output, stderr = process.communicate()
print output
print stderr, as appropriate.

OR are you trying to get this output on Windows? If so, you probably need
shell=True/

[ahe, 2012-11-05 09:58:11]

https://codereview.chromium.org/11228050/diff/1/tools/build.py
File tools/build.py (right):

https://codereview.chromium.org/11228050/diff/1/tools/build.py#newcode321
tools/build.py:321: process = subprocess.Popen(args, stderr=sys.stdout)
On 2012/10/29 16:17:56, Emily Fortuna wrote:
> On 2012/10/29 12:59:39, ahe wrote:
> > On 2012/10/23 16:46:17, Emily Fortuna wrote:
> > > On 2012/10/23 08:36:51, ahe wrote:
> > > > On 2012/10/23 08:34:15, Mads Ager wrote:
> > > > > Should this just be stderr=STDOUT?
> > > > 
> > > > That would be stderr=subprocess.STDOUT but that doesn't work.
> > > 
> > > Why does stderr=subprocess.STDOUT not work?
> > 
> > I don't know. We tried and it didn't work. However, it turned out that this
> > didn't work either.
> 
> alternatively:
> process = subprocess.Popen(args, stderr=subprocess.PIPE,
stdout=subprocess.PIPE)
> output, stderr = process.communicate()
> print output
> print stderr, as appropriate.

Unfortunately, that would be a severe regression compared to the current
behavior. We want to see output incrementally.
 
> OR are you trying to get this output on Windows? If so, you probably need
> shell=True/

Not that far yet. We were just trying to redirect stderr to stdout on Linux and
Mac.