diff --git a/src/header/pwd/mod.rs b/src/header/pwd/mod.rs
index 5a238a0a60..13af962835 100644
--- a/src/header/pwd/mod.rs
+++ b/src/header/pwd/mod.rs
@@ -1,4 +1,6 @@
-//! pwd implementation for relibc
+//! `pwd.h` implementation.
+//!
+//! See <https://pubs.opengroup.org/onlinepubs/9799919799/basedefs/pwd.h.html>.
 
 use alloc::{boxed::Box, vec::Vec};
 use core::{
@@ -30,6 +32,10 @@ const SEPARATOR: u8 = b':';
 #[cfg(target_os = "redox")]
 const SEPARATOR: u8 = b';';
 
+/// See <https://pubs.opengroup.org/onlinepubs/9799919799/basedefs/pwd.h.html>
+/// for POSIX minimum requirements, and
+/// <https://www.man7.org/linux/man-pages/man3/getpwnam.3.html> for further
+/// details.
 #[repr(C)]
 #[derive(Debug)]
 pub struct passwd {
@@ -213,6 +219,45 @@ unsafe fn mux(
     }
 }
 
+/// See <https://pubs.opengroup.org/onlinepubs/9799919799/functions/endpwent.html>.
+#[no_mangle]
+pub extern "C" fn endpwent() {
+    unsafe {
+        READER = None;
+    }
+}
+
+/// See <https://pubs.opengroup.org/onlinepubs/9799919799/functions/endpwent.html>.
+#[no_mangle]
+pub extern "C" fn getpwent() -> *mut passwd {
+    let reader = match unsafe { &mut READER } {
+        Some(reader) => reader,
+        None => {
+            let file = match File::open(c_str!("/etc/passwd"), fcntl::O_RDONLY) {
+                Ok(file) => file,
+                Err(_) => return ptr::null_mut(),
+            };
+            let reader = BufReader::new(file);
+            unsafe {
+                READER = Some(reader);
+                READER.as_mut().unwrap()
+            }
+        }
+    };
+    getpwent_r(reader, None)
+        .map(|res| res.into_global())
+        .unwrap_or(ptr::null_mut())
+}
+
+/// See <https://pubs.opengroup.org/onlinepubs/9799919799/functions/getpwnam.html>.
+#[no_mangle]
+pub extern "C" fn getpwnam(name: *const c_char) -> *mut passwd {
+    pwd_lookup(|parts| unsafe { strcmp(parts.pw_name, name) } == 0, None)
+        .map(|res| res.into_global())
+        .unwrap_or(ptr::null_mut())
+}
+
+/// See <https://pubs.opengroup.org/onlinepubs/9799919799/functions/getpwnam.html>.
 #[no_mangle]
 pub unsafe extern "C" fn getpwnam_r(
     name: *const c_char,
@@ -234,6 +279,15 @@ pub unsafe extern "C" fn getpwnam_r(
     )
 }
 
+/// See <https://pubs.opengroup.org/onlinepubs/9799919799/functions/getpwuid.html>.
+#[no_mangle]
+pub extern "C" fn getpwuid(uid: uid_t) -> *mut passwd {
+    pwd_lookup(|parts| parts.pw_uid == uid, None)
+        .map(|res| res.into_global())
+        .unwrap_or(ptr::null_mut())
+}
+
+/// See <https://pubs.opengroup.org/onlinepubs/9799919799/functions/getpwuid.html>.
 #[no_mangle]
 pub unsafe extern "C" fn getpwuid_r(
     uid: uid_t,
@@ -256,51 +310,10 @@ pub unsafe extern "C" fn getpwuid_r(
     )
 }
 
-#[no_mangle]
-pub extern "C" fn getpwnam(name: *const c_char) -> *mut passwd {
-    pwd_lookup(|parts| unsafe { strcmp(parts.pw_name, name) } == 0, None)
-        .map(|res| res.into_global())
-        .unwrap_or(ptr::null_mut())
-}
-
-#[no_mangle]
-pub extern "C" fn getpwuid(uid: uid_t) -> *mut passwd {
-    pwd_lookup(|parts| parts.pw_uid == uid, None)
-        .map(|res| res.into_global())
-        .unwrap_or(ptr::null_mut())
-}
-
-#[no_mangle]
-pub extern "C" fn getpwent() -> *mut passwd {
-    let reader = match unsafe { &mut READER } {
-        Some(reader) => reader,
-        None => {
-            let file = match File::open(c_str!("/etc/passwd"), fcntl::O_RDONLY) {
-                Ok(file) => file,
-                Err(_) => return ptr::null_mut(),
-            };
-            let reader = BufReader::new(file);
-            unsafe {
-                READER = Some(reader);
-                READER.as_mut().unwrap()
-            }
-        }
-    };
-    getpwent_r(reader, None)
-        .map(|res| res.into_global())
-        .unwrap_or(ptr::null_mut())
-}
-
+/// See <https://pubs.opengroup.org/onlinepubs/9799919799/functions/endpwent.html>.
 #[no_mangle]
 pub extern "C" fn setpwent() {
     if let Some(reader) = unsafe { &mut READER } {
         let _ = reader.seek(SeekFrom::Start(0));
     }
 }
-
-#[no_mangle]
-pub extern "C" fn endpwent() {
-    unsafe {
-        READER = None;
-    }
-}