Remove -x in python distutils shell script

[wjwwood]

This prevents extraneous output in the installation step. According to the man page:

http://heirloom.sourceforge.net/sh/sh.1.html

-x Print commands and their arguments as they are executed.

This is the same as activating BASH_XTRACEFD (http://linux.die.net/man/1/sh). This is the type of output it prevents:

+ '[' -n '' ']'
+ cd /Users/william/jade/src/catkin
+ /usr/bin/env PYTHONPATH=/Users/william/jade/install/lib/python2.7/site-packages:/Users/william/jade/build/catkin/lib/python2.7/site-packages: CATKIN_BINARY_DIR=/Users/william/jade/build/catkin /usr/bin/python /Users/william/jade/src/catkin/setup.py build --build-base /Users/william/jade/build/catkin install --prefix=/Users/william/jade/install --install-scripts=/Users/william/jade/install/bin

The reason I noticed and tracked it down was because this is also output on stderr, which the catkin_tools command picked up on and reported as a warning (perhaps incorrectly).

[tfoote]

I'm not sure I'd call the outputs extraneous. That information is there so that you can see what exactly the build is running. There's no other way to get visibility into the internal state of this script unless it prints it out. This allows someone debugging the build to be able to reproduce it quite easily. Otherwise you'd only see the output of setup.py and never know what arguments or paths were passed to it when it was run.

[wjwwood]

@tfoote then we should use echo's as not to output on stderr for normal behavior, or run set -x only when a trace or debug environment variable is set, something like that.

Also, at least the first line or output is not very useful and honestly more confusing than helpful if you don't know where it is coming from: + '[' -n '' ']'

[dirk-thomas]

Using echo to print the major command instead of -x seems to be a good idea.

[wjwwood]

Ok, I added 8e2a948, but I'm still testing it in a bigger workspace now, and we should test it on Linux too.

[wjwwood]

Seems to work for me on Linux and OS X.

[tfoote]

+1

[dirk-thomas]

+1 I can confirm that the new messages go to stdout and stderr stay clean.

Since catkin has just been released into Indigo and Jade it will take a while until this patch appears in a patch release though.