memfd_createZ

pub fn memfd_createZ(name: [*:0]const u8, flags: u32) MemFdCreateError!fd_t {
    switch (native_os) {
        .linux => {
            // memfd_create is available only in glibc versions starting with 2.27 and bionic versions starting with 30.
            const use_c = std.c.versionCheck(if (builtin.abi.isAndroid()) .{ .major = 30, .minor = 0, .patch = 0 } else .{ .major = 2, .minor = 27, .patch = 0 });
            const sys = if (use_c) std.c else linux;
            const rc = sys.memfd_create(name, flags);
            switch (sys.errno(rc)) {
                .SUCCESS => return @intCast(rc),
                .FAULT => unreachable, // name has invalid memory
                .INVAL => return error.NameTooLong, // or, program has a bug and flags are faulty
                .NFILE => return error.SystemFdQuotaExceeded,
                .MFILE => return error.ProcessFdQuotaExceeded,
                .NOMEM => return error.OutOfMemory,
                else => |err| return unexpectedErrno(err),
            }
        },
        .freebsd => {
            if (comptime builtin.os.version_range.semver.max.order(.{ .major = 13, .minor = 0, .patch = 0 }) == .lt)
                @compileError("memfd_create is unavailable on FreeBSD < 13.0");
            const rc = system.memfd_create(name, flags);
            switch (errno(rc)) {
                .SUCCESS => return rc,
                .BADF => unreachable, // name argument NULL
                .INVAL => unreachable, // name too long or invalid/unsupported flags.
                .MFILE => return error.ProcessFdQuotaExceeded,
                .NFILE => return error.SystemFdQuotaExceeded,
                .NOSYS => return error.SystemOutdated,
                else => |err| return unexpectedErrno(err),
            }
        },
        else => @compileError("target OS does not support memfd_create()"),
    }
}