From 082660093584bffe39c5f12fec3a562bda373e20 Mon Sep 17 00:00:00 2001
From: Michael Daniels <mdaniels5757@gmail.com>
Date: Fri, 13 Mar 2026 22:02:56 -0400
Subject: [PATCH] man-pages: fix `can't resolve man7/groff_man.7` error when
 running `man man`

Fixes: #498875
---
 pkgs/by-name/ma/man-pages/package.nix | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/pkgs/by-name/ma/man-pages/package.nix b/pkgs/by-name/ma/man-pages/package.nix
index b8427e1ac992..be1ac104d5af 100644
--- a/pkgs/by-name/ma/man-pages/package.nix
+++ b/pkgs/by-name/ma/man-pages/package.nix
@@ -4,6 +4,7 @@
   fetchurl,
   directoryListingUpdater,
   gawk,
+  groff,
   man,
   pcre2,
   nixosTests,
@@ -27,6 +28,13 @@ stdenv.mkDerivation (finalAttrs: {
     hash = "sha256-0Y8hpgKwl3ilqQlr8b6EQbdzPpmBUEdKzPcD0WX06/Q=";
   };
 
+  # See https://git.kernel.org/pub/scm/docs/man-pages/man-pages.git/tree/man/man7/man.7,
+  # https://github.com/NixOS/nixpkgs/issues/498875
+  postPatch = ''
+    substituteInPlace man/man7/man.7 \
+      --replace-fail '.so man7/groff_man.7' '.so ${lib.getMan groff}/share/man/man7/groff_man.7'
+  '';
+
   nativeInstallCheckInputs = [
     gawk
     man