--- a/src/constants.rs	Tue Jun 24 18:11:38 2025 -0400
+++ b/src/constants.rs	Wed Jun 25 00:59:24 2025 -0400
@@ -6,6 +6,7 @@
 
 #[cfg(feature = "link")]
 use crate::libpam::pam_ffi;
+use crate::{_linklist, _man7, _manbsd, _xsso};
 use bitflags::bitflags;
 use libc::c_int;
 use num_enum::{IntoPrimitive, TryFromPrimitive};
@@ -145,11 +146,20 @@
     }
 }
 
-/// The Linux-PAM error return values. Success is an Ok [Result].
+/// The PAM error return codes.
+///
+/// These are returned by most PAM functions if an error of some kind occurs.
+///
+/// Instead of being an error code, success is represented by an Ok [`Result`].
 ///
-/// Most abbreviations (except `AuthTok` and `Max`) are now full words.
-/// For more detailed information, see
-/// `/usr/include/security/_pam_types.h`.
+/// # References
+///
+#[doc = _linklist!(pam: man7, manbsd)]
+/// - [X/SSO error code specification][xsso]
+///
+#[doc = _man7!(3 pam "RETURN_VALUES")]
+#[doc = _manbsd!(3 pam "RETURN%20VALUES")]
+#[doc = _xsso!("chap5.htm#tagcjh_06_02")]
 #[allow(non_camel_case_types, dead_code)]
 #[derive(Copy, Clone, Debug, PartialEq, TryFromPrimitive, IntoPrimitive)]
 #[non_exhaustive] // C might give us anything!
@@ -228,9 +238,6 @@
     }
 }
 
-/// Returned when text that should not have any `\0` bytes in it does.
-/// Analogous to [`std::ffi::NulError`], but the data it was created from
-/// is borrowed.
 #[cfg(test)]
 mod tests {
     use super::*;