Is it possible to "pass-through" GNU make jobserver environment to a submake served via a 3rd-party (non-make) -

when running gnu-make rules -jn make creates jobserver managing job-count across submakes. additionally can "pass jobserver environment" make recipe prefixing + - eg:

target :         +./some/complex/call/to/another/make target 

now instead of sub-make have (python) script runs complex packaging actions (too complex make). 1 of actions can run can spawn off make command.

package.stamp : $(deps)          +./packaging.py $(args)          touch $@ 

now when make command invoked inside packaging.py

make[1]: warning: jobserver unavailable: using -j1.  add `+' parent make rule. 

this makes sense because whatever environment setup make, may not being honoured or passed through python.

is possible pass through jobserver references through python program sub-make - if so, how?

there 2 aspects jobserver must preserved: first actual environment variable, make uses send options sub-makes. value being preserved properly, or else make not know should jobserver , not see warning message.

the second aspect 2 open file descriptors passed children of make. script must preserve these 2 descriptors , leave them open when invokes sub-make.

you don't show python code being used invoke sub-make. default, subprocess module not close file descriptors, can provide close_fds=true option have so... should not use option if want parallel make invocations work jobserver.

if you're not using subprocess, you'll have show are doing.

you should mark python tag it's python question.