Which operating systems support passing -j options to sub-makes?

Question

From the man page for gnu make:

The ‘-j’ option is a special case (see Parallel Execution). If you set it to some numeric value ‘N’ and your operating system supports it (most any UNIX system will; others typically won’t), the parent make and all the sub-makes will communicate to ensure that there are only ‘N’ jobs running at the same time between them all. Note that any job that is marked recursive (see Instead of Executing Recipes) doesn’t count against the total jobs (otherwise we could get ‘N’ sub-makes running and have no slots left over for any real work!)

If your operating system doesn’t support the above communication, then ‘-j 1’ is always put into MAKEFLAGS instead of the value you specified. This is because if the ‘-j’ option were passed down to sub-makes, you would get many more jobs running in parallel than you asked for. If you give ‘-j’ with no numeric argument, meaning to run as many jobs as possible in parallel, this is passed down, since multiple infinities are no more than one.

Which common operating systems support or don't support this behavior? And how can you tell if your os supports it?

The answer [here](http://stackoverflow.com/a/28994835/258523) covers this a bit. — Etan Reisner, Mar 13 '15 at 03:45
Thanks, that helps. I've edit the question to also ask how you can tell — Kat, Mar 13 '15 at 04:01

score 4 · Accepted Answer · answered Mar 13 '15 at 11:54

To tell if your make supports this, run this command from your shell prompt:

echo 'all:;@echo $(filter jobserver,$(.FEATURES))' | make -f-

If it prints 'jobserver', then you have support. If it prints nothing, you do not have support. Or, if your OS doesn't support echo or pipelines, create a small makefile containing:

all:;@echo $(filter jobserver,$(.FEATURES))

then run make with that makefile.

Which operating systems support passing -j options to sub-makes?

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