Randomize segment name generated for SharedArray.

[twadleigh]

Compensates for the lack of an analog of shm_unlink in Windows.

Addresses #10773.

[ViralBShah]

Cc: @amitmurthy

[amitmurthy]

On OSX, I get the error

while loading parallel.jl, in expression starting on line 30
    From worker 3:       * examples             in  13.07 seconds
ERROR: LoadError: LoadError: SystemError: shm_open() failed for /jl-073248-HwtDQWQkm64lrHd4tut6: File name too long
 in anonymous at task.jl:1388

I'll test it with a shorter name and identify the right length for which we can make it work.

[amitmurthy]

Can you update the PR with

shm_seg_name = @sprintf("/jl%06u%s", getpid() % 10^6, randstring(20)) ?

I just removed the -s and it now passes on OSX.

[twadleigh]

Done. I thought I had made it short enough. Thanks for checking.

[nalimilan]

Isn't the comment # On OSX, the shm_seg_name length must be < 32 characters wrong (or imprecise) then?

[amitmurthy]

Yes. the comment needs to be changed. Seems like < 30 is the right answer.

On Sun, Apr 19, 2015 at 8:42 PM, Milan Bouchet-Valat <
notifications@github.com> wrote:

Isn't the comment # On OSX, the shm_seg_name length must be < 32
characters wrong (or imprecise) then?

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Reply to this email directly or view it on GitHub
#10877 (comment).

[amitmurthy]

Corrected in master.

Found this - https://books.google.co.in/books?id=K8vUkpOXhN4C&lpg=PA1156&ots=OLjoTX_s0z&dq=osx%20shared%20memory%20name%20characters&pg=PA1156#v=onepage&q=osx%20shared%20memory%20name%20characters&f=false