diff --git a/AI.md b/AI.md
index 91fe6d5..7177677 100644
--- a/AI.md
+++ b/AI.md
@@ -1344,4 +1344,22 @@ Next patch number should be `0253`.
   dispatch code only because it is available, and prefer a small mars-nwe facade
   if several modules need the same helper pattern.
 
-Next patch number should be `0264`.
+
+## 2026-06-02 - Patch 0264 GPL-2.0-only source/header normalization
+
+- Normalize mars-nwe-owned `.c` and `.h` files to GPL-2.0-only.  Existing
+  GPL-2-or-later text should be rewritten to version 2 only, and files without
+  a license header should gain a project header.
+- C/header files should carry `SPDX-License-Identifier: GPL-2.0-only` at the
+  top.
+- Preserve/restore copyright attribution for Martin Stover and add current
+  maintenance attribution for Mario Fetka where missing.
+- Root `COPYING` should state the project-level GPL-2.0-only policy before the
+  full GNU GPL version 2 text.
+- `README` and `README.md` should describe the GPL-2.0-only policy and point to
+  `COPYING`.
+- Do not introduce GPLv3-or-later wording in mars-nwe-owned source/header files
+  or dependency documentation unless a separate explicit relicensing decision is
+  made.
+
+Next patch number should be `0265`.
diff --git a/COPYING b/COPYING
index a43ea21..8a4bdc1 100644
--- a/COPYING
+++ b/COPYING
@@ -1,3 +1,15 @@
+MARS_NWE license notice
+=======================
+
+The mars_nwe project sources are distributed under the GNU General Public
+License version 2 only (GPL-2.0-only), with no later-version grant.
+
+Source files should use the SPDX identifier:
+
+    SPDX-License-Identifier: GPL-2.0-only
+
+The full GNU GPL version 2 text follows.
+
 		    GNU GENERAL PUBLIC LICENSE
 		       Version 2, June 1991
 
diff --git a/README b/README
index d053e9a..796dfa6 100644
--- a/README
+++ b/README
@@ -4,9 +4,9 @@ written by Martin Stover, Marburg, Germany.
 >>>> Please read THE WHOLE of this file as it gives important
 >>>> information about mars_nwe, how you can get help and so on.
 
-This software is freely distributable under the GNU public license, a
-copy of which you should have received with this software (in a file
-called COPYING).
+This software is freely distributable under the GNU General Public
+License version 2 only (GPL-2.0-only), with no later-version grant.
+A copy of the GPL version 2 license text is in the file called COPYING.
 
 
 WHAT CAN MARS_NWE DO?
diff --git a/README.md b/README.md
index f58da0e..ff24c9b 100644
--- a/README.md
+++ b/README.md
@@ -16,6 +16,16 @@ Although MARS_NWE still builds and runs on modern Linux systems, it remains an o
 
 Known follow-up work is tracked in [`TODO.md`](TODO.md).
 
+## License
+
+MARS_NWE source files are normalized to the GNU General Public License
+version 2 only (GPL-2.0-only), with no later-version grant.  New and
+updated C source/header files should carry `SPDX-License-Identifier:
+GPL-2.0-only`, and root `COPYING` contains the GPL version 2 license text.
+
+Copyright attribution is kept for Martin Stover as the original author and
+for Mario Fetka for current maintenance work.
+
 ## About This Repository
 
 This repository was originally assembled to compare the differences between the more recent MARS_NWE versions, especially those not produced by the original author. Older versions going back to 0.96 were also imported to preserve development history and make it easier to track how the code changed over time.
diff --git a/REDESIGN.md b/REDESIGN.md
index 796d4a2..0dd5dee 100644
--- a/REDESIGN.md
+++ b/REDESIGN.md
@@ -2506,3 +2506,14 @@ For the ongoing endpoint documentation pass, keep doing the conservative thing:
 5. record real layout differences, but do not change behavior in the same patch.
 
 Functional cleanup should come later in small patches with tests.
+
+## Source license policy
+
+The mars-nwe-owned C source and header files are GPL-2.0-only, with no
+later-version grant.  New and updated mars-nwe-owned `.c` and `.h` files should
+carry `SPDX-License-Identifier: GPL-2.0-only` and keep copyright attribution for
+Martin Stover as the original author plus Mario Fetka for current maintenance
+work where project-level headers are added.
+
+Third-party imports remain under their own upstream licenses inside the relevant
+`third_party/` subtree and must be documented separately.
diff --git a/TODO.md b/TODO.md
index 70dc988..20c57ab 100644
--- a/TODO.md
+++ b/TODO.md
@@ -1969,3 +1969,22 @@ Follow-up:
   planned 4.x endpoint after the async synchronization group.  Keep active
   fall-through handlers intact when shared logic is intentional, and add only
   adjacent per-case Request/Response notes for documentation-only patches.
+
+### GPL-2.0-only source/header normalization
+
+Current status:
+
+- Patch `0264` normalizes mars-nwe-owned `.c` and `.h` files to
+  GPL-2.0-only and adds missing source/header license blocks.
+- Root `COPYING`, legacy `README`, and modern `README.md` document the project
+  license policy explicitly.
+- Copyright attribution should include Martin Stover for the historical code
+  base and Mario Fetka for current maintenance work where source/header files
+  carry project-level headers.
+
+Follow-up:
+
+- Keep future C/header additions on `SPDX-License-Identifier: GPL-2.0-only`.
+- When importing third-party code, keep its original license in the
+  corresponding `third_party/` subtree and document it separately rather than
+  mixing it into mars-nwe-owned source headers.
diff --git a/doc/old/config.h b/doc/old/config.h
index d24fc68..046e77d 100644
--- a/doc/old/config.h
+++ b/doc/old/config.h
@@ -1,3 +1,19 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * This file is part of mars_nwe.
+ *
+ * Copyright (C) 1993-2000 Martin Stover, Marburg, Germany
+ * Copyright (C) 2026 Mario Fetka
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 only.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
 /* config.h: 22-Jun-00 */
 /* some of this config is needed by make, others by cc                     */
 
diff --git a/include/connect.h b/include/connect.h
index 2870cf6..b223e01 100644
--- a/include/connect.h
+++ b/include/connect.h
@@ -1,3 +1,19 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * This file is part of mars_nwe.
+ *
+ * Copyright (C) 1993-2000 Martin Stover, Marburg, Germany
+ * Copyright (C) 2026 Mario Fetka
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 only.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
 /* connect.h 04-Apr-00 */
 #ifndef _CONNECT_H_
 #define _CONNECT_H_
diff --git a/include/debmask.h b/include/debmask.h
index 89db75d..b3ed8f2 100644
--- a/include/debmask.h
+++ b/include/debmask.h
@@ -1,3 +1,19 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * This file is part of mars_nwe.
+ *
+ * Copyright (C) 1993-2000 Martin Stover, Marburg, Germany
+ * Copyright (C) 2026 Mario Fetka
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 only.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
 /* debmask.h: 23-Jul-97 */
 #ifndef _DEBMASK_H_
 #define _DEBMASK_H_
diff --git a/include/emutli.h b/include/emutli.h
index aa7b598..44414be 100644
--- a/include/emutli.h
+++ b/include/emutli.h
@@ -1,11 +1,12 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
 /* emutli.h 18-Nov-99 */
 
 /* (C)opyright (C) 1993,1995  Martin Stover, Marburg, Germany
+ * Copyright (C) 2026 Mario Fetka
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
+ * the Free Software Foundation; version 2 only.
  *
  * This program is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
diff --git a/include/emutli1.h b/include/emutli1.h
index 5aeb22c..795412c 100644
--- a/include/emutli1.h
+++ b/include/emutli1.h
@@ -1,11 +1,12 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
 /* emutli1.h 05-May-98 */
 
 /* (C)opyright (C) 1993,1995  Martin Stover, Marburg, Germany
+ * Copyright (C) 2026 Mario Fetka
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
+ * the Free Software Foundation; version 2 only.
  *
  * This program is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
diff --git a/include/extpipe.h b/include/extpipe.h
index 39c7866..389c878 100644
--- a/include/extpipe.h
+++ b/include/extpipe.h
@@ -1,3 +1,19 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * This file is part of mars_nwe.
+ *
+ * Copyright (C) 1993-2000 Martin Stover, Marburg, Germany
+ * Copyright (C) 2026 Mario Fetka
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 only.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
 /* extpipe.h 31-Jul-98 */
 
 #ifndef _EXTPIPE_H_
diff --git a/include/ipx.h b/include/ipx.h
index 5f3476e..6264ef1 100644
--- a/include/ipx.h
+++ b/include/ipx.h
@@ -1,4 +1,19 @@
-/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * This file is part of mars_nwe.
+ *
+ * Copyright (C) 1993-2000 Martin Stover, Marburg, Germany
+ * Copyright (C) 2026 Mario Fetka
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 only.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
 #ifndef _IPX_H_
 #define _IPX_H_
 
diff --git a/include/namedos.h b/include/namedos.h
index 5c68b20..9dffbd0 100644
--- a/include/namedos.h
+++ b/include/namedos.h
@@ -1,3 +1,19 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * This file is part of mars_nwe.
+ *
+ * Copyright (C) 1993-2000 Martin Stover, Marburg, Germany
+ * Copyright (C) 2026 Mario Fetka
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 only.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
 /*
  * namedos.h: DOS namespace helpers for mars_nwe
  */
diff --git a/include/nameos2.h b/include/nameos2.h
index 7957f09..9d04ed9 100644
--- a/include/nameos2.h
+++ b/include/nameos2.h
@@ -1,7 +1,9 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
 /*
  * nameos2.h: 08-Aug-96
  *
  * (C)opyright (C) 1993,1996  Martin Stover, Marburg, Germany
+ * Copyright (C) 2026 Mario Fetka
  */
 #ifndef _NAMEOS2_H_
 #define _NAMEOS2_H_
diff --git a/include/namspace.h b/include/namspace.h
index c2a4746..13e5458 100644
--- a/include/namspace.h
+++ b/include/namspace.h
@@ -1,11 +1,12 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
 /* namspace.h 01-Feb-98 : NameSpace Services, mars_nwe */
 
 /* (C)opyright (C) 1993,1998  Martin Stover, Marburg, Germany
+ * Copyright (C) 2026 Mario Fetka
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
+ * the Free Software Foundation; version 2 only.
  *
  * This program is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
diff --git a/include/net.h b/include/net.h
index 15c1821..704c0ef 100644
--- a/include/net.h
+++ b/include/net.h
@@ -1,11 +1,12 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
 /* net.h 12-Jan-99 */
 
 /* (C)opyright (C) 1993,1996  Martin Stover, Marburg, Germany
+ * Copyright (C) 2026 Mario Fetka
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
+ * the Free Software Foundation; version 2 only.
  *
  * This program is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
diff --git a/include/net1.h b/include/net1.h
index 69a0288..093fdba 100644
--- a/include/net1.h
+++ b/include/net1.h
@@ -1,11 +1,12 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
 /* net1.h 19.09.99 */
 
 /* (C)opyright (C) 1993-99 Martin Stover, Marburg, Germany
+ * Copyright (C) 2026 Mario Fetka
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
+ * the Free Software Foundation; version 2 only.
  *
  * This program is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
diff --git a/include/nwarchive.h b/include/nwarchive.h
index 1e40bc7..cb53b60 100644
--- a/include/nwarchive.h
+++ b/include/nwarchive.h
@@ -1,3 +1,19 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * This file is part of mars_nwe.
+ *
+ * Copyright (C) 1993-2000 Martin Stover, Marburg, Germany
+ * Copyright (C) 2026 Mario Fetka
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 only.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
 /* nwarchive.h - mars_nwe private archive metadata helpers */
 #ifndef _NWARCHIVE_H_
 #define _NWARCHIVE_H_
diff --git a/include/nwatalk.h b/include/nwatalk.h
index 74252b8..845dd18 100644
--- a/include/nwatalk.h
+++ b/include/nwatalk.h
@@ -1,3 +1,19 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * This file is part of mars_nwe.
+ *
+ * Copyright (C) 1993-2000 Martin Stover, Marburg, Germany
+ * Copyright (C) 2026 Mario Fetka
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 only.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
 #ifndef _NWATALK_H_
 #define _NWATALK_H_
 
diff --git a/include/nwattrib.h b/include/nwattrib.h
index 7dcf8a0..99a0fc0 100644
--- a/include/nwattrib.h
+++ b/include/nwattrib.h
@@ -1,3 +1,19 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * This file is part of mars_nwe.
+ *
+ * Copyright (C) 1993-2000 Martin Stover, Marburg, Germany
+ * Copyright (C) 2026 Mario Fetka
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 only.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
 /* nwattrib.h  30-Apr-98 */
 
 #ifndef _NWATTRIB_H_
diff --git a/include/nwbind.h b/include/nwbind.h
index ba0e059..278632a 100644
--- a/include/nwbind.h
+++ b/include/nwbind.h
@@ -1,3 +1,19 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * This file is part of mars_nwe.
+ *
+ * Copyright (C) 1993-2000 Martin Stover, Marburg, Germany
+ * Copyright (C) 2026 Mario Fetka
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 only.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
 /* nwbind.h 23-Apr-98 */
 
 #ifndef _NWBIND_H_
diff --git a/include/nwconn.h b/include/nwconn.h
index 58aa6b6..1bd32df 100644
--- a/include/nwconn.h
+++ b/include/nwconn.h
@@ -1,3 +1,19 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * This file is part of mars_nwe.
+ *
+ * Copyright (C) 1993-2000 Martin Stover, Marburg, Germany
+ * Copyright (C) 2026 Mario Fetka
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 only.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
 /* nwconn.h 13-May-98 */
 #ifndef _NWCONN_H_
 #define _NWCONN_H_
diff --git a/include/nwcrypt.h b/include/nwcrypt.h
index 34a4517..036b4cb 100644
--- a/include/nwcrypt.h
+++ b/include/nwcrypt.h
@@ -1,3 +1,19 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * This file is part of mars_nwe.
+ *
+ * Copyright (C) 1993-2000 Martin Stover, Marburg, Germany
+ * Copyright (C) 2026 Mario Fetka
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 only.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
 /* nwcrypt.h 22-Jun-96 */
 extern void shuffle(unsigned char *lon,
                     const unsigned char *buf, int buflen,
diff --git a/include/nwdbm.h b/include/nwdbm.h
index dfe6e89..1c04be6 100644
--- a/include/nwdbm.h
+++ b/include/nwdbm.h
@@ -1,10 +1,11 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
 /* nwdbm.h 25-Apr-00 */
 /* (C)opyright (C) 1993,2000  Martin Stover, Marburg, Germany
+ * Copyright (C) 2026 Mario Fetka
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
+ * the Free Software Foundation; version 2 only.
  *
  * This program is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
diff --git a/include/nwfile.h b/include/nwfile.h
index 08df099..164e1e8 100644
--- a/include/nwfile.h
+++ b/include/nwfile.h
@@ -1,3 +1,19 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * This file is part of mars_nwe.
+ *
+ * Copyright (C) 1993-2000 Martin Stover, Marburg, Germany
+ * Copyright (C) 2026 Mario Fetka
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 only.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
 /* nwfile.h 10-Nov-99 */
 #ifndef _NWFILE_H_
 #define _NWFILE_H_
diff --git a/include/nwfname.h b/include/nwfname.h
index e47d27b..5a239f7 100644
--- a/include/nwfname.h
+++ b/include/nwfname.h
@@ -1,3 +1,19 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * This file is part of mars_nwe.
+ *
+ * Copyright (C) 1993-2000 Martin Stover, Marburg, Germany
+ * Copyright (C) 2026 Mario Fetka
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 only.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
 /* nwfname.h 17-Jun-97 */
 
 #ifndef _NWFNAME_H_
diff --git a/include/nwqconn.h b/include/nwqconn.h
index 930701b..e9f10a1 100644
--- a/include/nwqconn.h
+++ b/include/nwqconn.h
@@ -1,3 +1,19 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * This file is part of mars_nwe.
+ *
+ * Copyright (C) 1993-2000 Martin Stover, Marburg, Germany
+ * Copyright (C) 2026 Mario Fetka
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 only.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
 /* nwqconn.h 14-Apr-98 */
 #ifndef _NWQCONN_H_
 #define _NWQCONN_H_
diff --git a/include/nwqueue.h b/include/nwqueue.h
index 5799c0b..22c625b 100644
--- a/include/nwqueue.h
+++ b/include/nwqueue.h
@@ -1,3 +1,19 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * This file is part of mars_nwe.
+ *
+ * Copyright (C) 1993-2000 Martin Stover, Marburg, Germany
+ * Copyright (C) 2026 Mario Fetka
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 only.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
 /* nwqueue.h 14-Apr-98 */
 #ifndef _NWQUEUE_H_
 #define _NWQUEUE_H_
diff --git a/include/nwsalvage.h b/include/nwsalvage.h
index b96c2b4..39a0964 100644
--- a/include/nwsalvage.h
+++ b/include/nwsalvage.h
@@ -1,3 +1,19 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * This file is part of mars_nwe.
+ *
+ * Copyright (C) 1993-2000 Martin Stover, Marburg, Germany
+ * Copyright (C) 2026 Mario Fetka
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 only.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
 #ifndef _NWSALVAGE_H_
 #define _NWSALVAGE_H_
 
diff --git a/include/nwserv.h b/include/nwserv.h
index 6c45aa5..ead7129 100644
--- a/include/nwserv.h
+++ b/include/nwserv.h
@@ -1,10 +1,11 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
 /* nwserv.h 17-Jul-97 */
 /* (C)opyright (C) 1993,1995  Martin Stover, Marburg, Germany
+ * Copyright (C) 2026 Mario Fetka
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
+ * the Free Software Foundation; version 2 only.
  *
  * This program is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
diff --git a/include/nwshare.h b/include/nwshare.h
index 2aff3e1..e3d4f24 100644
--- a/include/nwshare.h
+++ b/include/nwshare.h
@@ -1,5 +1,7 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
 /* nwshare.h:  25-Sep-99*/
 /* (C)opyright (C) 1993-1999  Martin Stover, Marburg, Germany
+ * Copyright (C) 2026 Mario Fetka
  */
 
 #ifndef _NWSHARE_H_
diff --git a/include/nwvolume.h b/include/nwvolume.h
index a054572..35a3be6 100644
--- a/include/nwvolume.h
+++ b/include/nwvolume.h
@@ -1,10 +1,11 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
 /* nwvolume.h  09-Oct-99 */
 /* (C)opyright (C) 1993-1999  Martin Stover, Marburg, Germany
+ * Copyright (C) 2026 Mario Fetka
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
+ * the Free Software Foundation; version 2 only.
  *
  * This program is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
diff --git a/include/nwxattr.h b/include/nwxattr.h
index b578db1..a26790e 100644
--- a/include/nwxattr.h
+++ b/include/nwxattr.h
@@ -1,3 +1,19 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * This file is part of mars_nwe.
+ *
+ * Copyright (C) 1993-2000 Martin Stover, Marburg, Germany
+ * Copyright (C) 2026 Mario Fetka
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 only.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
 #ifndef _NWXATTR_H_
 #define _NWXATTR_H_
 
diff --git a/include/queuedef.h b/include/queuedef.h
index 0a05ad4..0e78541 100644
--- a/include/queuedef.h
+++ b/include/queuedef.h
@@ -1,3 +1,19 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * This file is part of mars_nwe.
+ *
+ * Copyright (C) 1993-2000 Martin Stover, Marburg, Germany
+ * Copyright (C) 2026 Mario Fetka
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 only.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
 /* queuedef.h 09-Aug-97 */
 
 #ifndef _QUEUEDEF_H_
diff --git a/include/sema.h b/include/sema.h
index 16b5325..f2c2345 100644
--- a/include/sema.h
+++ b/include/sema.h
@@ -1,3 +1,19 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * This file is part of mars_nwe.
+ *
+ * Copyright (C) 1993-2000 Martin Stover, Marburg, Germany
+ * Copyright (C) 2026 Mario Fetka
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 only.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
 /* sema.h: 07-Aug-97 */
 
 #ifndef _SEMA_H_
diff --git a/include/tools.h b/include/tools.h
index aade641..b5cd850 100644
--- a/include/tools.h
+++ b/include/tools.h
@@ -1,11 +1,12 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
 /*  tools.h : 18-Apr-00   */
 
 /* (C)opyright (C) 1993-2000  Martin Stover, Marburg, Germany
+ * Copyright (C) 2026 Mario Fetka
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
+ * the Free Software Foundation; version 2 only.
  *
  * This program is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
diff --git a/include/trustee.h b/include/trustee.h
index 067fe1c..5738e9c 100644
--- a/include/trustee.h
+++ b/include/trustee.h
@@ -1,3 +1,19 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * This file is part of mars_nwe.
+ *
+ * Copyright (C) 1993-2000 Martin Stover, Marburg, Germany
+ * Copyright (C) 2026 Mario Fetka
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 only.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
 /* trustee.h  13-Apr-00 */
 #ifndef _TRUSTEE_H_
 #define _TRUSTEE_H_
diff --git a/include/unxfile.h b/include/unxfile.h
index 30e87af..2da1477 100644
--- a/include/unxfile.h
+++ b/include/unxfile.h
@@ -1,10 +1,11 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
 /* unxfile.h:  23-Jul-98 */
 /* (C)opyright (C) 1993,1998  Martin Stover, Marburg, Germany
+ * Copyright (C) 2026 Mario Fetka
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
+ * the Free Software Foundation; version 2 only.
  *
  * This program is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
diff --git a/include/unxlog.h b/include/unxlog.h
index 20f49b8..fbc2212 100644
--- a/include/unxlog.h
+++ b/include/unxlog.h
@@ -1,3 +1,19 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * This file is part of mars_nwe.
+ *
+ * Copyright (C) 1993-2000 Martin Stover, Marburg, Germany
+ * Copyright (C) 2026 Mario Fetka
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 only.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
 /* unxlog.h */
 extern void write_utmp(int dologin, int connection, int pid,
                 ipxAddr_t *from_addr, uint8  *username);
diff --git a/opt/comm.c b/opt/comm.c
index f27773a..2f1199e 100644
--- a/opt/comm.c
+++ b/opt/comm.c
@@ -1,3 +1,19 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * This file is part of mars_nwe.
+ *
+ * Copyright (C) 1993-2000 Martin Stover, Marburg, Germany
+ * Copyright (C) 2026 Mario Fetka
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 only.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
 /* comm.c 22-Oct-98
  * simple demo for a command programm which do a
  * DOS/WIN <-> UNX command handling using PIPE filesystem.
diff --git a/opt/sendm.c b/opt/sendm.c
index 61d82b9..5eed6cc 100644
--- a/opt/sendm.c
+++ b/opt/sendm.c
@@ -1,3 +1,19 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * This file is part of mars_nwe.
+ *
+ * Copyright (C) 1993-2000 Martin Stover, Marburg, Germany
+ * Copyright (C) 2026 Mario Fetka
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 only.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
 /* sendm.c 23-Oct-96 */
 /*
  * simple demo for a sendmail acces under DOS
diff --git a/opt/unxcomm.c b/opt/unxcomm.c
index c5aa1bd..fdfc2cc 100644
--- a/opt/unxcomm.c
+++ b/opt/unxcomm.c
@@ -1,3 +1,19 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * This file is part of mars_nwe.
+ *
+ * Copyright (C) 1993-2000 Martin Stover, Marburg, Germany
+ * Copyright (C) 2026 Mario Fetka
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 only.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
 /* unxcomm.c 22-Oct-98 
  * simple UNX program to work together with 'comm'  
  * to demonstrate usage of pipefilesystem
diff --git a/opt/unxsendm.c b/opt/unxsendm.c
index 628be69..da94bcc 100644
--- a/opt/unxsendm.c
+++ b/opt/unxsendm.c
@@ -1,3 +1,19 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * This file is part of mars_nwe.
+ *
+ * Copyright (C) 1993-2000 Martin Stover, Marburg, Germany
+ * Copyright (C) 2026 Mario Fetka
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 only.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
 /* unxsendm.c 23-Oct-96 */
 /* simple UNX program to work together with 'pipe-filesystem'
  * and DOS sendm.exe to get sendmail functionality under DOS
diff --git a/opt/xsockrt.c b/opt/xsockrt.c
index f2ad4e9..9965b64 100644
--- a/opt/xsockrt.c
+++ b/opt/xsockrt.c
@@ -1,4 +1,6 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
 /* (C)opyright (C) 1997  Martin Stover, Marburg, Germany
+ * Copyright (C) 2026 Mario Fetka
  * simple program for adding/deleting ipx-routes for special sockets
  * e.g. for playing doom around ipx-networks.
  * needs special linux/net/ipx/af_ipx.c patch !!
diff --git a/src/connect.c b/src/connect.c
index 5eb1468..d0171d1 100644
--- a/src/connect.c
+++ b/src/connect.c
@@ -1,10 +1,11 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
 /* connect.c  15-Apr-00 */
 /* (C)opyright (C) 1993-2000, Martin Stover, Marburg, Germany
+ * Copyright (C) 2026 Mario Fetka
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
+ * the Free Software Foundation; version 2 only.
  *
  * This program is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
diff --git a/src/dbmtool.c b/src/dbmtool.c
index 76a1ddc..7b44e78 100644
--- a/src/dbmtool.c
+++ b/src/dbmtool.c
@@ -1,10 +1,11 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
 /* dbmtool.c  10-Nov-99  data base tool program for mars_nwe */
 /* (C)opyright (C) 1993,1995  Martin Stover, Marburg, Germany
+ * Copyright (C) 2026 Mario Fetka
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
+ * the Free Software Foundation; version 2 only.
  *
  * This program is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
diff --git a/src/empty.c b/src/empty.c
index e69de29..be6d443 100644
--- a/src/empty.c
+++ b/src/empty.c
@@ -0,0 +1,16 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * This file is part of mars_nwe.
+ *
+ * Copyright (C) 1993-2000 Martin Stover, Marburg, Germany
+ * Copyright (C) 2026 Mario Fetka
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 only.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
diff --git a/src/emutli.c b/src/emutli.c
index a83ebd3..a3d6c2e 100644
--- a/src/emutli.c
+++ b/src/emutli.c
@@ -1,14 +1,15 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
 /* emutli.c 04-Apr-00 */
 /*
  * One short try to emulate TLI with SOCKETS.
  */
 
 /* (C)opyright (C) 1993,1996 Martin Stover, Marburg, Germany
+ * Copyright (C) 2026 Mario Fetka
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
+ * the Free Software Foundation; version 2 only.
  *
  * This program is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
diff --git a/src/emutli1.c b/src/emutli1.c
index b5cd0b3..712a4ed 100644
--- a/src/emutli1.c
+++ b/src/emutli1.c
@@ -1,14 +1,15 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
 /* emutli1.c 05-May-98 */
 /*
  * One short try to emulate TLI with SOCKETS.
  */
 
 /* (C)opyright (C) 1993,1996 Martin Stover, Marburg, Germany
+ * Copyright (C) 2026 Mario Fetka
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
+ * the Free Software Foundation; version 2 only.
  *
  * This program is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
diff --git a/src/extpipe.c b/src/extpipe.c
index 6b9b2d4..d4b6f04 100644
--- a/src/extpipe.c
+++ b/src/extpipe.c
@@ -1,10 +1,11 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
 /* extpipe.c 03-Aug-98       */
 /* (C)opyright (C) 1993,1996  Martin Stover, Marburg, Germany
+ * Copyright (C) 2026 Mario Fetka
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
+ * the Free Software Foundation; version 2 only.
  *
  * This program is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
diff --git a/src/ftrustee.c b/src/ftrustee.c
index f365f11..ba711f0 100644
--- a/src/ftrustee.c
+++ b/src/ftrustee.c
@@ -1,10 +1,11 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
 /* ftrustee.c, 19.09.99 */
 /* (C)opyright (C) 1999  Martin Stover, Marburg, Germany
+ * Copyright (C) 2026 Mario Fetka
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
+ * the Free Software Foundation; version 2 only.
  *
  * This program is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
diff --git a/src/ipxif.c b/src/ipxif.c
index 308e59f..d0bc43d 100644
--- a/src/ipxif.c
+++ b/src/ipxif.c
@@ -1,3 +1,19 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * This file is part of mars_nwe.
+ *
+ * Copyright (C) 1993-2000 Martin Stover, Marburg, Germany
+ * Copyright (C) 2026 Mario Fetka
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 only.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
 /* inserted by Boris Popov <bp@butya.kz> */
 #include <sys/param.h>
 #include <sys/ioctl.h>
diff --git a/src/namedos.c b/src/namedos.c
index 2aa6b03..dd4c644 100644
--- a/src/namedos.c
+++ b/src/namedos.c
@@ -1,3 +1,19 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * This file is part of mars_nwe.
+ *
+ * Copyright (C) 1993-2000 Martin Stover, Marburg, Germany
+ * Copyright (C) 2026 Mario Fetka
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 only.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
 /* namedos.c : NameSpace DOS Services, mars_nwe
  *
  * Adds DOS 8.3 alias generation/resolution for long filenames on DOS
diff --git a/src/nameos2.c b/src/nameos2.c
index 26bde9e..140e53e 100644
--- a/src/nameos2.c
+++ b/src/nameos2.c
@@ -1,10 +1,11 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
 /* nameos2.c 14-May-97 : NameSpace OS2 Services, mars_nwe */
 /* (C)opyright (C) 1993,1996  Martin Stover, Marburg, Germany
+ * Copyright (C) 2026 Mario Fetka
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
+ * the Free Software Foundation; version 2 only.
  *
  * This program is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
diff --git a/src/namspace.c b/src/namspace.c
index 9f157c3..351a0b3 100644
--- a/src/namspace.c
+++ b/src/namspace.c
@@ -1,14 +1,15 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
 /* namspace.c 07-Oct-00 : NameSpace Services, mars_nwe */
 
 /* !!!!!!!!!!!! NOTE !!!!!!!!!! */
 /* Its still dirty, but it should work fairly well */
 
 /* (C)opyright (C) 1993,2000  Martin Stover, Marburg, Germany
+ * Copyright (C) 2026 Mario Fetka
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
+ * the Free Software Foundation; version 2 only.
  *
  * This program is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
diff --git a/src/ncpserv.c b/src/ncpserv.c
index 503eb64..ca895dd 100644
--- a/src/ncpserv.c
+++ b/src/ncpserv.c
@@ -1,10 +1,11 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
 /* ncpserv.c 29-Jul-97 */
 /* (C)opyright (C) 1993,1996  Martin Stover, Marburg, Germany
+ * Copyright (C) 2026 Mario Fetka
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
+ * the Free Software Foundation; version 2 only.
  *
  * This program is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
diff --git a/src/net1.c b/src/net1.c
index 1f55200..51d8374 100644
--- a/src/net1.c
+++ b/src/net1.c
@@ -1,11 +1,12 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
 /* net1.c, 19.09.99 */
 
 /* (C)opyright (C) 1993-99  Martin Stover, Marburg, Germany
+ * Copyright (C) 2026 Mario Fetka
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
+ * the Free Software Foundation; version 2 only.
  *
  * This program is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
diff --git a/src/nwarchive.c b/src/nwarchive.c
index 7e0cd67..f1f4bff 100644
--- a/src/nwarchive.c
+++ b/src/nwarchive.c
@@ -1,3 +1,19 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * This file is part of mars_nwe.
+ *
+ * Copyright (C) 1993-2000 Martin Stover, Marburg, Germany
+ * Copyright (C) 2026 Mario Fetka
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 only.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
 /* nwarchive.c - mars_nwe private archive metadata helpers */
 #include "net.h"
 #include "nwarchive.h"
diff --git a/src/nwatalk.c b/src/nwatalk.c
index 0750cd4..aa30aa4 100644
--- a/src/nwatalk.c
+++ b/src/nwatalk.c
@@ -1,3 +1,19 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * This file is part of mars_nwe.
+ *
+ * Copyright (C) 1993-2000 Martin Stover, Marburg, Germany
+ * Copyright (C) 2026 Mario Fetka
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 only.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
 /* mars_nwe AFP xattr metadata backend helpers. */
 #include "net.h"
 #include "config.h"
diff --git a/src/nwattrib.c b/src/nwattrib.c
index aa49e1b..6606232 100644
--- a/src/nwattrib.c
+++ b/src/nwattrib.c
@@ -1,10 +1,11 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
 /* nwattrib.c 07-Oct-00 */
 /* (C)opyright (C) 1998,2000  Martin Stover, Marburg, Germany
+ * Copyright (C) 2026 Mario Fetka
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
+ * the Free Software Foundation; version 2 only.
  *
  * This program is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
diff --git a/src/nwbind.c b/src/nwbind.c
index e595dd0..1c129d0 100644
--- a/src/nwbind.c
+++ b/src/nwbind.c
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
 /* nwbind.c */
 
 #ifndef MARS_NWE_BUILD_DATE
@@ -8,11 +9,11 @@
 /* authentification and some message and queue handling */
 
 /* (C)opyright (C) 1993,2000  Martin Stover, Marburg, Germany
+ * Copyright (C) 2026 Mario Fetka
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
+ * the Free Software Foundation; version 2 only.
  *
  * This program is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
diff --git a/src/nwclient.c b/src/nwclient.c
index 358809c..dff2b2b 100644
--- a/src/nwclient.c
+++ b/src/nwclient.c
@@ -1,3 +1,4 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
 /* nwclient.c: 10-Feb-96 */
 /*
  * Einfacher Testclient, wird von nwserv (im Client Modus) gestartet
@@ -8,11 +9,11 @@
  */
 
 /* (C)opyright (C) 1993,1995  Martin Stover, Marburg, Germany
+ * Copyright (C) 2026 Mario Fetka
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
+ * the Free Software Foundation; version 2 only.
  *
  * This program is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
diff --git a/src/nwconn.c b/src/nwconn.c
index cc84985..94a1f78 100644
--- a/src/nwconn.c
+++ b/src/nwconn.c
@@ -1,12 +1,13 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
 /* nwconn.c 18-Apr-00       */
 /* one process / connection */
 
 /* (C)opyright (C) 1993,2000  Martin Stover, Marburg, Germany
+ * Copyright (C) 2026 Mario Fetka
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
+ * the Free Software Foundation; version 2 only.
  *
  * This program is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
diff --git a/src/nwcrypt.c b/src/nwcrypt.c
index 633abff..19ad2a8 100644
--- a/src/nwcrypt.c
+++ b/src/nwcrypt.c
@@ -1,3 +1,19 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * This file is part of mars_nwe.
+ *
+ * Copyright (C) 1993-2000 Martin Stover, Marburg, Germany
+ * Copyright (C) 2026 Mario Fetka
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 only.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
 /*$*********************************************************
 $*
 $* This code has been taken from DDJ 11/93, from an
diff --git a/src/nwdbm.c b/src/nwdbm.c
index 333d52e..bc51b84 100644
--- a/src/nwdbm.c
+++ b/src/nwdbm.c
@@ -1,10 +1,11 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
 /* nwdbm.c  25-Apr-00 data base for mars_nwe */
 /* (C)opyright (C) 1993,2000  Martin Stover, Marburg, Germany
+ * Copyright (C) 2026 Mario Fetka
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
+ * the Free Software Foundation; version 2 only.
  *
  * This program is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
diff --git a/src/nwfile.c b/src/nwfile.c
index b804236..3fb6d53 100644
--- a/src/nwfile.c
+++ b/src/nwfile.c
@@ -1,10 +1,11 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
 /* nwfile.c  25-Apr-00 */
 /* (C)opyright (C) 1993-2000  Martin Stover, Marburg, Germany
+ * Copyright (C) 2026 Mario Fetka
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
+ * the Free Software Foundation; version 2 only.
  *
  * This program is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
diff --git a/src/nwfname.c b/src/nwfname.c
index 9eb6601..4779545 100644
--- a/src/nwfname.c
+++ b/src/nwfname.c
@@ -1,10 +1,11 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
 /* nwfname.c 17-Jun-97 */
 /* (C)opyright (C) 1997  Martin Stover, Marburg, Germany
+ * Copyright (C) 2026 Mario Fetka
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
+ * the Free Software Foundation; version 2 only.
  *
  * This program is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
diff --git a/src/nwqconn.c b/src/nwqconn.c
index 90e174e..410b878 100644
--- a/src/nwqconn.c
+++ b/src/nwqconn.c
@@ -1,10 +1,11 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
 /* nwqconn.c 15-Sep-99 */
 /* (C)opyright (C) 1997  Martin Stover, Marburg, Germany
+ * Copyright (C) 2026 Mario Fetka
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
+ * the Free Software Foundation; version 2 only.
  *
  * This program is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
diff --git a/src/nwqueue.c b/src/nwqueue.c
index ea48c4f..52229da 100644
--- a/src/nwqueue.c
+++ b/src/nwqueue.c
@@ -1,10 +1,11 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
 /* nwqueue.c 04-Jun-98       */
 /* (C)opyright (C) 1993,1996  Martin Stover, Marburg, Germany
+ * Copyright (C) 2026 Mario Fetka
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
+ * the Free Software Foundation; version 2 only.
  *
  * This program is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
diff --git a/src/nwroute.c b/src/nwroute.c
index 7b4cdb4..ba25579 100644
--- a/src/nwroute.c
+++ b/src/nwroute.c
@@ -1,10 +1,11 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
 /* nwroute.c 18-Apr-00 */
 /* (C)opyright (C) 1993,2000  Martin Stover, Marburg, Germany
+ * Copyright (C) 2026 Mario Fetka
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
+ * the Free Software Foundation; version 2 only.
  *
  * This program is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
diff --git a/src/nwroute1.c b/src/nwroute1.c
index fe454a6..d8f50fc 100644
--- a/src/nwroute1.c
+++ b/src/nwroute1.c
@@ -1,10 +1,11 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
 /* nwroute1.c 17-Jul-97 */
 /* (C)opyright (C) 1993,1995  Martin Stover, Marburg, Germany
+ * Copyright (C) 2026 Mario Fetka
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
+ * the Free Software Foundation; version 2 only.
  *
  * This program is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
diff --git a/src/nwrouted.c b/src/nwrouted.c
index 6dcb935..31020b5 100644
--- a/src/nwrouted.c
+++ b/src/nwrouted.c
@@ -1,3 +1,19 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * This file is part of mars_nwe.
+ *
+ * Copyright (C) 1993-2000 Martin Stover, Marburg, Germany
+ * Copyright (C) 2026 Mario Fetka
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 only.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
 /* nwrouted.c */
 #define IN_NWROUTED  1
 #include "nwroute.c"
diff --git a/src/nwsalvage.c b/src/nwsalvage.c
index d56575f..6dca0c5 100644
--- a/src/nwsalvage.c
+++ b/src/nwsalvage.c
@@ -1,3 +1,19 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * This file is part of mars_nwe.
+ *
+ * Copyright (C) 1993-2000 Martin Stover, Marburg, Germany
+ * Copyright (C) 2026 Mario Fetka
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 only.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
 /* nwsalvage.c - NetWare salvage/recycle backend helpers */
 #include "nwsalvage.h"
 
diff --git a/src/nwserv.c b/src/nwserv.c
index 01a93d9..8cb25db 100644
--- a/src/nwserv.c
+++ b/src/nwserv.c
@@ -1,12 +1,13 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
 /* nwserv.c 19-May-98 */
 /* MAIN Prog for NWSERV + NWROUTED  */
 
 /* (C)opyright (C) 1993,1998  Martin Stover, Marburg, Germany
+ * Copyright (C) 2026 Mario Fetka
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
+ * the Free Software Foundation; version 2 only.
  *
  * This program is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
diff --git a/src/nwshare.c b/src/nwshare.c
index 31165dd..f1014bb 100644
--- a/src/nwshare.c
+++ b/src/nwshare.c
@@ -1,11 +1,11 @@
-
+/* SPDX-License-Identifier: GPL-2.0-only */
 /* nwshare.c, 13-Apr-00 */
 /* (C)opyright (C) 1993-2000  Martin Stover, Marburg, Germany
+ * Copyright (C) 2026 Mario Fetka
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
+ * the Free Software Foundation; version 2 only.
  *
  * This program is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
diff --git a/src/nwvolume.c b/src/nwvolume.c
index eb3627c..3f72be0 100644
--- a/src/nwvolume.c
+++ b/src/nwvolume.c
@@ -1,10 +1,11 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
 /* nwvolume.c  01-Sep-00 */
 /* (C)opyright (C) 1993-2000  Martin Stover, Marburg, Germany
+ * Copyright (C) 2026 Mario Fetka
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
+ * the Free Software Foundation; version 2 only.
  *
  * This program is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
diff --git a/src/nwxattr.c b/src/nwxattr.c
index c42216d..74a79c7 100644
--- a/src/nwxattr.c
+++ b/src/nwxattr.c
@@ -1,3 +1,19 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * This file is part of mars_nwe.
+ *
+ * Copyright (C) 1993-2000 Martin Stover, Marburg, Germany
+ * Copyright (C) 2026 Mario Fetka
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 only.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
 /* nwxattr.c - mars_nwe extended attribute namespace helpers */
 #include "config.h"
 #include "nwxattr.h"
diff --git a/src/sema.c b/src/sema.c
index 584ff2e..ed98a97 100644
--- a/src/sema.c
+++ b/src/sema.c
@@ -1,13 +1,14 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
 /* sema.c :07-Aug-97 */
 
 /* simple semaphore emulation, needs more work */
 
 /* (C)opyright (C) 1997 Martin Stover, Marburg, Germany
+ * Copyright (C) 2026 Mario Fetka
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
+ * the Free Software Foundation; version 2 only.
  *
  * This program is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
diff --git a/src/tools.c b/src/tools.c
index 5ea9918..4098427 100644
--- a/src/tools.c
+++ b/src/tools.c
@@ -1,10 +1,11 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
 /* tools.c  18-Apr-00 */
 /* (C)opyright (C) 1993-2000  Martin Stover, Marburg, Germany
+ * Copyright (C) 2026 Mario Fetka
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
+ * the Free Software Foundation; version 2 only.
  *
  * This program is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
diff --git a/src/trustee.c b/src/trustee.c
index 4118900..5fcc705 100644
--- a/src/trustee.c
+++ b/src/trustee.c
@@ -1,10 +1,11 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
 /* trustee.c 15-Apr-00 */
 /* (C)opyright (C) 1998,2000  Martin Stover, Marburg, Germany
+ * Copyright (C) 2026 Mario Fetka
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
+ * the Free Software Foundation; version 2 only.
  *
  * This program is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
diff --git a/src/unxfile.c b/src/unxfile.c
index 49d48e7..6be80d9 100644
--- a/src/unxfile.c
+++ b/src/unxfile.c
@@ -1,11 +1,12 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
 /* unxfile.c:  15-Aug-00 */
 
 /* (C)opyright (C) 1993,2000  Martin Stover, Marburg, Germany
+ * Copyright (C) 2026 Mario Fetka
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
+ * the Free Software Foundation; version 2 only.
  *
  * This program is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
diff --git a/src/unxlog.c b/src/unxlog.c
index 6d24446..aed2df4 100644
--- a/src/unxlog.c
+++ b/src/unxlog.c
@@ -1,10 +1,11 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
 /* unxlog.c : 11-Jul-98 */
 /* (C)opyright (C) 1993,1996  Martin Stover, Marburg, Germany
+ * Copyright (C) 2026 Mario Fetka
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
+ * the Free Software Foundation; version 2 only.
  *
  * This program is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
diff --git a/sys/comm.c b/sys/comm.c
index 3ac9d37..e3b90c1 100644
--- a/sys/comm.c
+++ b/sys/comm.c
@@ -1 +1,17 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * This file is part of mars_nwe.
+ *
+ * Copyright (C) 1993-2000 Martin Stover, Marburg, Germany
+ * Copyright (C) 2026 Mario Fetka
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 only.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
 #include "../opt/comm.c"
diff --git a/tests/afp/afp_create_directory_smoke.c b/tests/afp/afp_create_directory_smoke.c
index da2cce2..bf320ad 100644
--- a/tests/afp/afp_create_directory_smoke.c
+++ b/tests/afp/afp_create_directory_smoke.c
@@ -1,3 +1,19 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * This file is part of mars_nwe.
+ *
+ * Copyright (C) 1993-2000 Martin Stover, Marburg, Germany
+ * Copyright (C) 2026 Mario Fetka
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 only.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
 /*
  * Linux smoke test for NetWare AFP Create Directory.
  *
diff --git a/tests/afp/afp_create_file_smoke.c b/tests/afp/afp_create_file_smoke.c
index 7cfe954..1a1af7c 100644
--- a/tests/afp/afp_create_file_smoke.c
+++ b/tests/afp/afp_create_file_smoke.c
@@ -1,3 +1,19 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * This file is part of mars_nwe.
+ *
+ * Copyright (C) 1993-2000 Martin Stover, Marburg, Germany
+ * Copyright (C) 2026 Mario Fetka
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 only.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
 /*
  * Linux smoke test for NetWare AFP Create File.
  *
diff --git a/tests/afp/afp_delete_smoke.c b/tests/afp/afp_delete_smoke.c
index a97b504..485c171 100644
--- a/tests/afp/afp_delete_smoke.c
+++ b/tests/afp/afp_delete_smoke.c
@@ -1,3 +1,19 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * This file is part of mars_nwe.
+ *
+ * Copyright (C) 1993-2000 Martin Stover, Marburg, Germany
+ * Copyright (C) 2026 Mario Fetka
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 only.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
 /*
  * Linux smoke test for NetWare AFP Delete.
  *
diff --git a/tests/afp/afp_deleted_info_smoke.c b/tests/afp/afp_deleted_info_smoke.c
index d95541c..c1ad149 100644
--- a/tests/afp/afp_deleted_info_smoke.c
+++ b/tests/afp/afp_deleted_info_smoke.c
@@ -1,3 +1,19 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * This file is part of mars_nwe.
+ *
+ * Copyright (C) 1993-2000 Martin Stover, Marburg, Germany
+ * Copyright (C) 2026 Mario Fetka
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 only.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
 /*
  * Linux smoke test for AFP 0x13 Get Macintosh Info On Deleted File.
  */
diff --git a/tests/afp/afp_dos_name_smoke.c b/tests/afp/afp_dos_name_smoke.c
index 35ee0c5..7195c7a 100644
--- a/tests/afp/afp_dos_name_smoke.c
+++ b/tests/afp/afp_dos_name_smoke.c
@@ -1,3 +1,19 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * This file is part of mars_nwe.
+ *
+ * Copyright (C) 1993-2000 Martin Stover, Marburg, Germany
+ * Copyright (C) 2026 Mario Fetka
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 only.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
 /*
  * Linux smoke test for NetWare AFP Get DOS Name From Entry ID.
  */
diff --git a/tests/afp/afp_entry_id_smoke.c b/tests/afp/afp_entry_id_smoke.c
index 0e102f9..de8d2b2 100644
--- a/tests/afp/afp_entry_id_smoke.c
+++ b/tests/afp/afp_entry_id_smoke.c
@@ -1,3 +1,19 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * This file is part of mars_nwe.
+ *
+ * Copyright (C) 1993-2000 Martin Stover, Marburg, Germany
+ * Copyright (C) 2026 Mario Fetka
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 only.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
 /*
  * Linux smoke test for NetWare AFP Entry ID path lookup.
  *
diff --git a/tests/afp/afp_file_fork_io_smoke.c b/tests/afp/afp_file_fork_io_smoke.c
index 449d0a9..9cec5b1 100644
--- a/tests/afp/afp_file_fork_io_smoke.c
+++ b/tests/afp/afp_file_fork_io_smoke.c
@@ -1,3 +1,19 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * This file is part of mars_nwe.
+ *
+ * Copyright (C) 1993-2000 Martin Stover, Marburg, Germany
+ * Copyright (C) 2026 Mario Fetka
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 only.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
 /*
  * Smoke test for NetWare AFP data-fork I/O.
  *
diff --git a/tests/afp/afp_file_info_smoke.c b/tests/afp/afp_file_info_smoke.c
index 8ed5762..52e2730 100644
--- a/tests/afp/afp_file_info_smoke.c
+++ b/tests/afp/afp_file_info_smoke.c
@@ -1,3 +1,19 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * This file is part of mars_nwe.
+ *
+ * Copyright (C) 1993-2000 Martin Stover, Marburg, Germany
+ * Copyright (C) 2026 Mario Fetka
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 only.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
 /*
  * Linux smoke test for NetWare AFP Get File Information.
  */
diff --git a/tests/afp/afp_open_file_fork_smoke.c b/tests/afp/afp_open_file_fork_smoke.c
index df2cd99..dbdfdfc 100644
--- a/tests/afp/afp_open_file_fork_smoke.c
+++ b/tests/afp/afp_open_file_fork_smoke.c
@@ -1,3 +1,19 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * This file is part of mars_nwe.
+ *
+ * Copyright (C) 1993-2000 Martin Stover, Marburg, Germany
+ * Copyright (C) 2026 Mario Fetka
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 only.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
 /*
  * Linux smoke test for NetWare AFP Open File Fork.
  *
diff --git a/tests/afp/afp_rename_smoke.c b/tests/afp/afp_rename_smoke.c
index 27ba4b1..8e973b7 100644
--- a/tests/afp/afp_rename_smoke.c
+++ b/tests/afp/afp_rename_smoke.c
@@ -1,3 +1,19 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * This file is part of mars_nwe.
+ *
+ * Copyright (C) 1993-2000 Martin Stover, Marburg, Germany
+ * Copyright (C) 2026 Mario Fetka
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 only.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
 /*
  * Linux smoke test for NetWare AFP Rename.
  *
diff --git a/tests/afp/afp_scan_info_smoke.c b/tests/afp/afp_scan_info_smoke.c
index f199703..bed72fa 100644
--- a/tests/afp/afp_scan_info_smoke.c
+++ b/tests/afp/afp_scan_info_smoke.c
@@ -1,3 +1,19 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * This file is part of mars_nwe.
+ *
+ * Copyright (C) 1993-2000 Martin Stover, Marburg, Germany
+ * Copyright (C) 2026 Mario Fetka
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 only.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
 /*
  * Linux smoke test for NetWare AFP Scan File Information.
  */
diff --git a/tests/afp/afp_set_file_info_smoke.c b/tests/afp/afp_set_file_info_smoke.c
index f38c0cb..2adecfe 100644
--- a/tests/afp/afp_set_file_info_smoke.c
+++ b/tests/afp/afp_set_file_info_smoke.c
@@ -1,3 +1,19 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * This file is part of mars_nwe.
+ *
+ * Copyright (C) 1993-2000 Martin Stover, Marburg, Germany
+ * Copyright (C) 2026 Mario Fetka
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 only.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
 /*
  * Linux smoke test for NetWare AFP Set File Information metadata writes.
  */
diff --git a/tests/afp/afp_temp_dir_handle_smoke.c b/tests/afp/afp_temp_dir_handle_smoke.c
index 4577cd7..1f3ad28 100644
--- a/tests/afp/afp_temp_dir_handle_smoke.c
+++ b/tests/afp/afp_temp_dir_handle_smoke.c
@@ -1,3 +1,19 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * This file is part of mars_nwe.
+ *
+ * Copyright (C) 1993-2000 Martin Stover, Marburg, Germany
+ * Copyright (C) 2026 Mario Fetka
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 only.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
 /*
  * Linux smoke test for NetWare AFP Alloc Temporary Directory Handle.
  *
diff --git a/tests/salvage/ncp_delete_smoke.c b/tests/salvage/ncp_delete_smoke.c
index 19d0409..0b4192d 100644
--- a/tests/salvage/ncp_delete_smoke.c
+++ b/tests/salvage/ncp_delete_smoke.c
@@ -1,3 +1,19 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * This file is part of mars_nwe.
+ *
+ * Copyright (C) 1993-2000 Martin Stover, Marburg, Germany
+ * Copyright (C) 2026 Mario Fetka
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 only.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
 /*
  * Linux smoke helper for classic NetWare file create/delete.
  *
diff --git a/tests/salvage/ncp_read_smoke.c b/tests/salvage/ncp_read_smoke.c
index d677f02..8498506 100644
--- a/tests/salvage/ncp_read_smoke.c
+++ b/tests/salvage/ncp_read_smoke.c
@@ -1,3 +1,19 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * This file is part of mars_nwe.
+ *
+ * Copyright (C) 1993-2000 Martin Stover, Marburg, Germany
+ * Copyright (C) 2026 Mario Fetka
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 only.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
 /*
  * Linux smoke helper for reading a NetWare file through ncpfs/ncplib.
  *
diff --git a/tests/salvage/ncp_salvage_purge_smoke.c b/tests/salvage/ncp_salvage_purge_smoke.c
index 57f50fa..59e6473 100644
--- a/tests/salvage/ncp_salvage_purge_smoke.c
+++ b/tests/salvage/ncp_salvage_purge_smoke.c
@@ -1,3 +1,19 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * This file is part of mars_nwe.
+ *
+ * Copyright (C) 1993-2000 Martin Stover, Marburg, Germany
+ * Copyright (C) 2026 Mario Fetka
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 only.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
 /*
  * Linux smoke helper for NCP 87/18 Purge Salvageable File.
  *
diff --git a/tests/salvage/ncp_salvage_recover_smoke.c b/tests/salvage/ncp_salvage_recover_smoke.c
index e6c4833..85f1e96 100644
--- a/tests/salvage/ncp_salvage_recover_smoke.c
+++ b/tests/salvage/ncp_salvage_recover_smoke.c
@@ -1,3 +1,19 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * This file is part of mars_nwe.
+ *
+ * Copyright (C) 1993-2000 Martin Stover, Marburg, Germany
+ * Copyright (C) 2026 Mario Fetka
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 only.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
 /*
  * Linux smoke helper for NCP 87/17 Recover Salvageable File.
  *
diff --git a/tests/salvage/ncp_salvage_scan_smoke.c b/tests/salvage/ncp_salvage_scan_smoke.c
index 051c063..c21a4e1 100644
--- a/tests/salvage/ncp_salvage_scan_smoke.c
+++ b/tests/salvage/ncp_salvage_scan_smoke.c
@@ -1,3 +1,19 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * This file is part of mars_nwe.
+ *
+ * Copyright (C) 1993-2000 Martin Stover, Marburg, Germany
+ * Copyright (C) 2026 Mario Fetka
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 only.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
 /*
  * Linux smoke helper for NCP 87/16 Scan Salvageable Files.
  *