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Comment by oseityphelysiol | Hacker News Reader

Of all the quirks with process spawning in posix keeping file descriptors open is the most problematic one I encountered. This bit into my ass while implementing a C library to have proper process spawning and stdio handling in LUA. I really wish file descriptors were non inheritable by default.

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> I really wish file descriptors were non inheritable by default.

In Python 3.4, they are (released ten years ago).

But in POSIX, they are not, so any module implemented in C is still potentially problematic.

Only if that C-implemented module uses raw C to create file descriptors. And if the module has not gotten an update in the past ten years to fix the problem.

This can help: https://man7.org/linux/man-pages/man2/close_range.2.html

    close_range(3, ~0U, CLOSE_RANGE_UNSHARE);
    execve(....);

...but it's not very portable yet.

I’ve never heard of it before. I work in an embedded environment where kernel version is known beforehand, so portability won’t be an issue. Thanks.

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