Running Pkg.dir in IJulia throws StateError("Resource temporarily unavailable")

[jiahao]

In[1]: Pkg.dir("IJulia")
Out[1]: 
"/Users/jiahao/.julia/IJulia"
ERROR: StateError("Resource temporarily unavailable")
 in recv at /Users/jiahao/.julia/ZMQ/src/ZMQ.jl:492
 in recv_ipython at /Users/jiahao/.julia/IJulia/src/msg.jl:61
 in eventloop at /Users/jiahao/.julia/IJulia/src/IJulia.jl:66
 in anonymous at multi.jl:1308

This reproduces reliably on my IJulia instance and IJulia is completely unresponsive after this error is thrown.

[stevengj]

I'm seeing this error for various other random things as well (e.g. using PyPlot). It seems to have been introduced by a recent commit in Julia.

[StefanKarpinski]

Yeah, I'm getting this too.

[stevengj]

git bisect seems to think the error started with JuliaLang/julia@2a56b19 by @JeffBezanson ... not sure how this could be related.

[stevengj]

We do use errno().... the problem could occur if errno() is somehow not giving the right result at https://github.com/JuliaLang/ZMQ.jl/blob/master/src/ZMQ.jl#L486-L491

[stevengj]

On MacOS X, the errno in errno.h is not a global variable, it is defined as:

extern int * __error(void);
#define errno (*__error())

so Julia's new way of getting errno is wrong. Looks like Jeff's patch needs to be reverted.