System Calls & File I/O in Zig

Use bun.sys instead of std.fs or std.posix for cross-platform syscalls with proper error handling.

bun.sys.File (Preferred)

For most file operations, use the bun.sys.File wrapper:

const File = bun.sys.File;

const file = switch (File.open(path, bun.O.RDWR, 0o644)) {
    .result => |f| f,
    .err => |err| return .{ .err = err },
};
defer file.close();

// Read/write
_ = try file.read(buffer).unwrap();