Fix race condition in Makefile

[ek9852]

Fix the following error:

make install
./uninstall-opencv.sh
make: execvp: ./uninstall-opencv.sh: Text file busy
Makefile:27: recipe for target 'uninstallopencv' failed
make: *** [uninstallopencv] Error 127

The problem is that Makefile will run in parallel,
and chmod and execvp just run at the same time will
trigger this. git support +x natively.
Just checkin the code with +x permission and remove
the chmod hack in the Makefile

[jjo-in-pdx]

make doesn't run in parallel unless you run at make -jN with N>1... Are you seeing something different? On what system?

GNU make knows how to execute several recipes at once. Normally, make will execute only one recipe at a time, waiting for it to finish before executing the next. However, the ‘-j’ or ‘--jobs’ option tells make to execute many recipes simultaneously.
https://www.gnu.org/software/make/manual/html_node/Parallel.html

[ek9852]

Saw in an AWS docker. Anyway the chmod in a Makefile is a hack, why not just change the attribute in git. 2018-03-08 14:27 GMT-08:00 John ONeill <notifications@github.com>:

…

make doesn't run in parallel unless you run at make -jN with N>1... Are you seeing something different? On what system? GNU make knows how to execute several recipes at once. Normally, make will execute only one recipe at a time, waiting for it to finish before executing the next. However, the ‘-j’ or ‘--jobs’ option tells make to execute many recipes simultaneously. https://www.gnu.org/software/make/manual/html_node/Parallel.html — You are receiving this because you authored the thread. Reply to this email directly, view it on GitHub <#12 (comment)>, or mute the thread <https://github.com/notifications/unsubscribe-auth/AGJz6xdPqk6oSZ0H_z8RSVqfEdUX2Owvks5tcbBugaJpZM4ShFM6> .

[jjo-in-pdx]

I forgot to thank you, @ek9852 , for the submissions on this as well, so thanks again. I did a search on AWS running make in parallel and didn't find anything. I will discuss this request, but doing a search for GitHub executable permissions shows lots of issues people have had, a fair amount had to do with Windows and Unix/Linux/Mac cross platform complications that we would want to avoid.

Are you able to run NCS natively on Darwin/Mac OS ? Somebody asked that on the #11 (comment) but I didn't see an answer.

[ek9852]

It can at least built the api and use it on MBP, but not everything builts.
chmod is fast and after a few times tries the race condition might go though. But If this is a problem, this is a problem and we have the log.
I don't understand why "executable permissions shows lots of issues", it does not make sense to me.

[molyswu]

Hi,
Make a CNN model on examples caffe or tensorflow ,how to set the number of SHAVE ?

Thanks for your help!

[oraoto]

I encounter the same problem when building the Docker images. Some quick search leads to this sync hack: moby/moby#9547 (comment)

.PHONY: uninstallopencv
uninstallopencv:
	sync
	./uninstall-opencv.sh