```zig
const std = @import("../std.zig");
usingnamespace std.c;

extern "c" fn __error() *c_int;
pub const _errno = __error;

pub extern "c" fn getdents(fd: c_int, buf_ptr: [*]u8, nbytes: usize) usize;
pub extern "c" fn sigaltstack(ss: ?*stack_t, old_ss: ?*stack_t) c_int;
pub extern "c" fn getrandom(buf_ptr: [*]u8, buf_len: usize, flags: c_uint) isize;
```

Add missing C dl_iterate_phdr function for FreeBSD
user
```zig
const std = @import("../std.zig");
usingnamespace std.c;

extern "c" fn __error() *c_int;
pub const _errno = __error;

pub extern "c" fn getdents(fd: c_int, buf_ptr: [*]u8, nbytes: usize) usize;
pub extern "c" fn sigaltstack(ss: ?*stack_t, old_ss: ?*stack_t) c_int;
pub extern "c" fn getrandom(buf_ptr: [*]u8, buf_len: usize, flags: c_uint) isize;

pub const dl_iterate_phdr_callback = extern fn (info: *dl_phdr_info, size: usize, data: ?*c_void) c_int;
pub extern "c" fn dl_iterate_phdr(callback: dl_iterate_phdr_callback, data: ?*c_void) c_int;
```
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