refactor: change name arg of memfd_create() to &NixPath #2431
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| libc::memfd_create(cstr.as_ptr(), flags.bits()) | ||
| } else { | ||
| libc::syscall(libc::SYS_memfd_create, name.as_ptr(), flags.bits()) | ||
| libc::syscall(libc::SYS_memfd_create, cstr.as_ptr(), flags.bits()) |
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Is it possible we always use the else branch? Or does it have any drawback?
From tokio-rs/tracing#1879 I'm afraid that using libc::memfd_create may fail on some old GNU toolchain.
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Right, because the glibc wrapper may only be available since a specific version, and if you are using an older glibc and this Nix wrapper, the code won't compile. But raw syscalls are inherently unsafe, Nix tries to avoid it if possible.
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Honestly, this kind of thing has always been bothering me. I just created a tracking issue #2538 for these interfaces. May I ask about the issue you encountered with this?
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the issue you encountered with this?
Not in real-world, but a blocker I don't use nix at fast/logforth#80 (memfd.rs)
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Perhaps we should wrap the raw syscall. 😪
If we want to discuss this further, let's discuss it there #2538.
What does this PR do
nameargument ofmemfd_create()from&CStrto&NixPath.Add a test for(Update: The test was removed because the symbolmemfd_create().memfd_createis not available under our QEMU test and I cannot find a way to stop the linker from involving it)Checklist:
CONTRIBUTING.mdBreaking changes
This is not a breaking change, since
CStrhasNixPathimplemented.