Switch to SPDX identifiers.

Generated with

	sed -i 's|Copyright.*Andre Noll.*|SPDX-License-Identifier: GPL-2.0 */|g' *.c *.h

followed by manually tweaking the result a bit. No license change intended.

128 files changed, 139 insertions, 138 deletions

diff --git a/aac_afh.c b/aac_afh.c
index c5121af3..f7d25fed 100644
--- a/aac_afh.c
+++ b/aac_afh.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 2006 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
+/* SPDX-License-Identifier: GPL-2.0 */
 /*
  * based in parts on libfaad, Copyright (C) 2003-2005 M. Bakker,
  * Ahead Software AG
diff --git a/aacdec_filter.c b/aacdec_filter.c
index 656a1ea3..fa50814b 100644
--- a/aacdec_filter.c
+++ b/aacdec_filter.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 2006 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
+/* SPDX-License-Identifier: GPL-2.0 */
 /*
  * based in parts on libfaad, Copyright (C) 2003-2005 M. Bakker,
  * Ahead Software AG
diff --git a/afh.c b/afh.c
index 703418fa..d80b68c4 100644
--- a/afh.c
+++ b/afh.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 2008 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
+/* SPDX-License-Identifier: GPL-2.0 */
 
 /** \file afh.c The audio format handler tool.
  *
diff --git a/afh.h b/afh.h
index 2a1ec519..0fb6ba2f 100644
--- a/afh.h
+++ b/afh.h
@@ -1,4 +1,4 @@
-/* Copyright (C) 2005 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
+/* SPDX-License-Identifier: GPL-2.0 */
 
 /** \file afh.h Audio format handlers
  *
diff --git a/afh_common.c b/afh_common.c
index 7708706e..3c6e8064 100644
--- a/afh_common.c
+++ b/afh_common.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 1997 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
+/* SPDX-License-Identifier: GPL-2.0 */
 
 /** \file afh_common.c Common audio format handler functions. */
 
diff --git a/afh_recv.c b/afh_recv.c
index f6107a09..304945f1 100644
--- a/afh_recv.c
+++ b/afh_recv.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 2011 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
+/* SPDX-License-Identifier: GPL-2.0 */
 
 /** \file afh_recv.c Receiver for streaming local files. */
 
diff --git a/afs.c b/afs.c
index 44041980..023b3cfe 100644
--- a/afs.c
+++ b/afs.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 2007 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
+/* SPDX-License-Identifier: GPL-2.0 */
 
 /**
  * \file afs.c The implementation of the audio file selector.
diff --git a/afs.h b/afs.h
index 6d2b5692..505bdee3 100644
--- a/afs.h
+++ b/afs.h
@@ -1,4 +1,4 @@
-/* Copyright (C) 2007 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
+/* SPDX-License-Identifier: GPL-2.0 */
 
 /** \file afs.h The audio file selector API.
  *
diff --git a/aft.c b/aft.c
index 1185ed86..c4421348 100644
--- a/aft.c
+++ b/aft.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 2007 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
+/* SPDX-License-Identifier: GPL-2.0 */
 
 /** \file aft.c Audio file table functions. */
 
diff --git a/alsa_mix.c b/alsa_mix.c
index a6d50c11..936ffae7 100644
--- a/alsa_mix.c
+++ b/alsa_mix.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 2012 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
+/* SPDX-License-Identifier: GPL-2.0 */
 
 /** \file alsa_mix.c The ALSA mixer plugin. */
 
diff --git a/alsa_write.c b/alsa_write.c
index 94923f29..e0ab553b 100644
--- a/alsa_write.c
+++ b/alsa_write.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 2005 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
+/* SPDX-License-Identifier: GPL-2.0 */
 
 /** \file alsa_write.c paraslash's alsa output plugin */
 
diff --git a/amp_filter.c b/amp_filter.c
index dcef0c6f..1970a45a 100644
--- a/amp_filter.c
+++ b/amp_filter.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 2009 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
+/* SPDX-License-Identifier: GPL-2.0 */
 
 /** \file amp_filter.c Paraslash's amplify filter. */
 
diff --git a/ao_write.c b/ao_write.c
index 86080ae7..ca2b35ad 100644
--- a/ao_write.c
+++ b/ao_write.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 2011 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
+/* SPDX-License-Identifier: GPL-2.0 */
 
 /** \file ao_write.c Paraslash's libao output plugin. */
 
diff --git a/attribute.c b/attribute.c
index 876b04ce..efaeb617 100644
--- a/attribute.c
+++ b/attribute.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 1997 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
+/* SPDX-License-Identifier: GPL-2.0 */
 
 /** \file attribute.c Attribute handling functions. */
 
diff --git a/audioc.c b/audioc.c
index bf261845..b4638bfa 100644
--- a/audioc.c
+++ b/audioc.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 2005 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
+/* SPDX-License-Identifier: GPL-2.0 */
 
 /** \file audioc.c The client program used to connect to para_audiod(1).
  *
diff --git a/audiod.c b/audiod.c
index 29e84f13..6c2f6534 100644
--- a/audiod.c
+++ b/audiod.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 2005 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
+/* SPDX-License-Identifier: GPL-2.0 */
 
 /** \file audiod.c The paraslash's audio daemon.
  *
diff --git a/audiod.h b/audiod.h
index a9274764..4c182974 100644
--- a/audiod.h
+++ b/audiod.h
@@ -1,4 +1,4 @@
-/* Copyright (C) 2006 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
+/* SPDX-License-Identifier: GPL-2.0 */
 
 /** \file audiod.h Symbols exported from audiod.c. */
 
diff --git a/audiod_command.c b/audiod_command.c
index e5c6d3a9..65b1b71f 100644
--- a/audiod_command.c
+++ b/audiod_command.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 2005 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
+/* SPDX-License-Identifier: GPL-2.0 */
 
 /** \file audiod_command.c Commands for para_audiod. */
 
diff --git a/bash_completion b/bash_completion
index c3de2181..72839a8e 100644
--- a/bash_completion
+++ b/bash_completion
@@ -1,4 +1,4 @@
-# Copyright (C) 2007 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING.
+# SPDX-License-Identifier: GPL-2.0
 
 _para_complete()
 {
diff --git a/blob.c b/blob.c
index 24818f3b..71168434 100644
--- a/blob.c
+++ b/blob.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 2007 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
+/* SPDX-License-Identifier: GPL-2.0 */
 
 /** \file blob.c Macros and functions for blob handling. */
 
diff --git a/buffer_tree.c b/buffer_tree.c
index 3c60975d..3770a98a 100644
--- a/buffer_tree.c
+++ b/buffer_tree.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 2009 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
+/* SPDX-License-Identifier: GPL-2.0 */
 
 /** \file buffer_tree.c Buffer tree and buffer pool implementations. */
 
diff --git a/buffer_tree.h b/buffer_tree.h
index 3da92ec3..ea0d060d 100644
--- a/buffer_tree.h
+++ b/buffer_tree.h
@@ -1,4 +1,4 @@
-/* Copyright (C) 2009 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
+/* SPDX-License-Identifier: GPL-2.0 */
 
 /** \file buffer_tree.h Buffer trees, buffer tree nodes and buffer pools.
  *
diff --git a/client.c b/client.c
index 78402946..e1f148f8 100644
--- a/client.c
+++ b/client.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 1997 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
+/* SPDX-License-Identifier: GPL-2.0 */
 
 /** \file client.c The client program used to connect to para_server.
  *
diff --git a/client.h b/client.h
index 029031e1..e7b5fa5b 100644
--- a/client.h
+++ b/client.h
@@ -1,4 +1,4 @@
-/* Copyright (C) 1997 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
+/* SPDX-License-Identifier: GPL-2.0 */
 
 /** \file client.h Common client functions and exported symbols from client_common.c. */
 
diff --git a/client_common.c b/client_common.c
index d920fca5..3a6255e9 100644
--- a/client_common.c
+++ b/client_common.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 1997 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
+/* SPDX-License-Identifier: GPL-2.0 */
 
 /** \file client_common.c Common functions of para_client and para_audiod. */
 
diff --git a/color.c b/color.c
index 0e2beeb0..14071b97 100644
--- a/color.c
+++ b/color.c
@@ -1,3 +1,5 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+
 /** \file color.c Functions for printing colored messages. */
 
 /*
diff --git a/color.h b/color.h
index 167c9294..b5c7a4b8 100644
--- a/color.h
+++ b/color.h
@@ -1,5 +1,6 @@
-/** \file color.h Exported functions from color.c. */
+/* SPDX-License-Identifier: GPL-2.0 */
 
+/** \file color.h Exported functions from color.c. */
 
 /** "\033[1;38;5;2xx;48;5;2xxm\0" is 23 bytes */
 #define COLOR_MAXLEN 24
diff --git a/command.c b/command.c
index 6fe8e167..1be78eff 100644
--- a/command.c
+++ b/command.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 1997 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
+/* SPDX-License-Identifier: GPL-2.0 */
 
 /** \file command.c Client authentication and server commands. */
 
diff --git a/command.h b/command.h
index d71bc2c6..bf1bbea0 100644
--- a/command.h
+++ b/command.h
@@ -1,3 +1,5 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+
 /** \file command.h The structure of server and afs commands. */
 
 /** Per connection data available to command handlers. */
diff --git a/compress_filter.c b/compress_filter.c
index 61347312..5ccbc4b2 100644
--- a/compress_filter.c
+++ b/compress_filter.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 2005 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
+/* SPDX-License-Identifier: GPL-2.0 */
 
 /** \file compress_filter.c Paraslash's dynamic audio range compressor. */
 
diff --git a/crypt.h b/crypt.h
index 586b3c8b..2855f41f 100644
--- a/crypt.h
+++ b/crypt.h
@@ -1,4 +1,4 @@
-/* Copyright (C) 2005 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
+/* SPDX-License-Identifier: GPL-2.0 */
 
 /** \file crypt.h Crypto API.
  *
diff --git a/crypt_backend.h b/crypt_backend.h
index 10806cfc..d8e0086e 100644
--- a/crypt_backend.h
+++ b/crypt_backend.h
@@ -1,4 +1,4 @@
-/* Copyright (C) 2011 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
+/* SPDX-License-Identifier: GPL-2.0 */
 
 /** \file crypt_backend.h Non-public crypto interface. */
 
diff --git a/crypt_common.c b/crypt_common.c
index a60a2333..589e52df 100644
--- a/crypt_common.c
+++ b/crypt_common.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 2005 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
+/* SPDX-License-Identifier: GPL-2.0 */
 
 /** \file crypt_common.c Crypto functions independent of openssl/libgcrypt. */
 
diff --git a/daemon.c b/daemon.c
index d2506dd0..89158bb5 100644
--- a/daemon.c
+++ b/daemon.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 1997 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
+/* SPDX-License-Identifier: GPL-2.0 */
 
 /** \file daemon.c Some helpers for programs that detach from the console. */
 
diff --git a/daemon.h b/daemon.h
index 54879924..4a27f2b3 100644
--- a/daemon.h
+++ b/daemon.h
@@ -1,5 +1,6 @@
-/** \file daemon.h exported symbols from daemon.c */
+/* SPDX-License-Identifier: GPL-2.0 */
 
+/** \file daemon.h exported symbols from daemon.c */
 
 int daemonize(bool parent_waits);
 void daemon_open_log_or_die(void);
diff --git a/error.h b/error.h
index 91cf88a2..abed11c7 100644
--- a/error.h
+++ b/error.h
@@ -1,4 +1,4 @@
-/* Copyright (C) 2006 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
+/* SPDX-License-Identifier: GPL-2.0 */
 
 /** \file error.h List of error codes and messages. */
 
diff --git a/exec.c b/exec.c
index 01ad30b1..ec041353 100644
--- a/exec.c
+++ b/exec.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 2003 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
+/* SPDX-License-Identifier: GPL-2.0 */
 
 /** \file exec.c Helper functions for spawning new processes. */
 
diff --git a/fd.c b/fd.c
index 1eaa5550..a7608ffa 100644
--- a/fd.c
+++ b/fd.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 2006 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
+/* SPDX-License-Identifier: GPL-2.0 */
 
 /** \file fd.c Helper functions for file descriptor handling. */
 
diff --git a/fd.h b/fd.h
index baf80d33..1d04ecb9 100644
--- a/fd.h
+++ b/fd.h
@@ -1,4 +1,4 @@
-/* Copyright (C) 2006 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
+/* SPDX-License-Identifier: GPL-2.0 */
 
 /** \file fd.h exported symbols from fd.c */
 
diff --git a/fecdec_filter.c b/fecdec_filter.c
index fb7ddec3..4e3fa72b 100644
--- a/fecdec_filter.c
+++ b/fecdec_filter.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 2009 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
+/* SPDX-License-Identifier: GPL-2.0 */
 
 /** \file fecdec_filter.c A filter that fec-decodes an audio stream. */
 
diff --git a/file_write.c b/file_write.c
index a7085a20..4b63f7c5 100644
--- a/file_write.c
+++ b/file_write.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 2006 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
+/* SPDX-License-Identifier: GPL-2.0 */
 
 /** \file file_write.c simple output plugin for testing purposes */
 
diff --git a/filter.c b/filter.c
index 43d130d1..eb687558 100644
--- a/filter.c
+++ b/filter.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 2005 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
+/* SPDX-License-Identifier: GPL-2.0 */
 
 /** \file filter.c The stand-alone filter program.
  *
diff --git a/filter.h b/filter.h
index 4e3019b4..27e8d066 100644
--- a/filter.h
+++ b/filter.h
@@ -1,4 +1,4 @@
-/* Copyright (C) 2005 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
+/* SPDX-License-Identifier: GPL-2.0 */
 
 /** \file filter.h Filter API
  *
diff --git a/filter_common.c b/filter_common.c
index 2d2ef1eb..90fc5165 100644
--- a/filter_common.c
+++ b/filter_common.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 2005 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
+/* SPDX-License-Identifier: GPL-2.0 */
 
 /** \file filter_common.c Common helper functions for filter input/output. */
 
diff --git a/flac_afh.c b/flac_afh.c
index 860247f0..c63c3550 100644
--- a/flac_afh.c
+++ b/flac_afh.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 2011 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
+/* SPDX-License-Identifier: GPL-2.0 */
 
 /** \file flac_afh.c Audio format handler for flac files. */
 
diff --git a/flacdec_filter.c b/flacdec_filter.c
index dd4e7a74..a4504cc3 100644
--- a/flacdec_filter.c
+++ b/flacdec_filter.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 2011 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
+/* SPDX-License-Identifier: GPL-2.0 */
 
 /** \file flacdec_filter.c The flac decoder. */
 
diff --git a/gcc-compat.h b/gcc-compat.h
index 575a729a..2fa524a9 100644
--- a/gcc-compat.h
+++ b/gcc-compat.h
@@ -1,3 +1,5 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+
 #define __noreturn __attribute__ ((noreturn))
 #define __malloc __attribute__ ((malloc))
 #define __a_unused __attribute__ ((unused))
diff --git a/gcrypt.c b/gcrypt.c
index eab31f64..9baa6904 100644
--- a/gcrypt.c
+++ b/gcrypt.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 2011 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
+/* SPDX-License-Identifier: GPL-2.0 */
 
 /** \file gcrypt.c Libgrcypt-based encryption/decryption routines. */
 
diff --git a/grab_client.c b/grab_client.c
index 6f1b7d48..36d702f9 100644
--- a/grab_client.c
+++ b/grab_client.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 2006 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
+/* SPDX-License-Identifier: GPL-2.0 */
 
 /** \file grab_client.c Functions for grabbing the audio stream. */
 
diff --git a/grab_client.h b/grab_client.h
index 9bc01864..b38cced4 100644
--- a/grab_client.h
+++ b/grab_client.h
@@ -1,4 +1,4 @@
-/* Copyright (C) 2006 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
+/* SPDX-License-Identifier: GPL-2.0 */
 
 /** \file grab_client.h exported symbols from grab_client.c */
 
diff --git a/gui.c b/gui.c
index 9464e066..783dea1e 100644
--- a/gui.c
+++ b/gui.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 1998 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
+/* SPDX-License-Identifier: GPL-2.0 */
 
 /** \file gui.c Curses-based user interface.
  *
diff --git a/gui.h b/gui.h
index d8685818..5c704588 100644
--- a/gui.h
+++ b/gui.h
@@ -1,4 +1,4 @@
-/* Copyright (C) 2007 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
+/* SPDX-License-Identifier: GPL-2.0 */
 
 /** \file gui.h symbols used by gui and gui_theme */
 
diff --git a/gui_theme.c b/gui_theme.c
index 7899eeee..e510d392 100644
--- a/gui_theme.c
+++ b/gui_theme.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 2005 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
+/* SPDX-License-Identifier: GPL-2.0 */
 
 /** \file gui_theme.c Theme definitions. */
 
diff --git a/http.h b/http.h
index 112053b6..6e1d238c 100644
--- a/http.h
+++ b/http.h
@@ -1,3 +1,5 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+
 /** \file http.h macros used by http_send and http_recv */
 
 /** sent by the http sender to the client */
diff --git a/http_recv.c b/http_recv.c
index a7e0e1b2..9e72641e 100644
--- a/http_recv.c
+++ b/http_recv.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 2005 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
+/* SPDX-License-Identifier: GPL-2.0 */
 
 /** \file http_recv.c paraslash's http receiver */
 
diff --git a/http_send.c b/http_send.c
index 0ec23514..5a6dff0c 100644
--- a/http_send.c
+++ b/http_send.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 2005 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
+/* SPDX-License-Identifier: GPL-2.0 */
 
 /** \file http_send.c paraslash's http sender */
 
diff --git a/interactive.c b/interactive.c
index c37b5bd1..c3378e58 100644
--- a/interactive.c
+++ b/interactive.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 2011 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
+/* SPDX-License-Identifier: GPL-2.0 */
 
 /** \file interactive.c Readline abstraction for interactive sessions. */
 
diff --git a/interactive.h b/interactive.h
index 3c8b42fa..316f9495 100644
--- a/interactive.h
+++ b/interactive.h
@@ -1,4 +1,4 @@
-/* Copyright (C) 2011 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
+/* SPDX-License-Identifier: GPL-2.0 */
 
 /** \file interactive.h Interactive sessions based on the GNU readline library.
  *
diff --git a/ipc.c b/ipc.c
index b434960f..ea55572a 100644
--- a/ipc.c
+++ b/ipc.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 2006 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
+/* SPDX-License-Identifier: GPL-2.0 */
 
 /** \file ipc.c Inter-process communication and shared memory helpers. */
 
diff --git a/ipc.h b/ipc.h
index c4437104..a09612d5 100644
--- a/ipc.h
+++ b/ipc.h
@@ -1,3 +1,5 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+
 /** \file ipc.h inter process communication and shared memory routines */
 
 /** possible values for shm_attach() */
diff --git a/list.h b/list.h
index 82f5b36d..84051b6b 100644
--- a/list.h
+++ b/list.h
@@ -1,11 +1,9 @@
-/*
- * Copied from the Linux kernel source tree, version 2.6.13.
- *
- * Licensed under the GPL v2 as per the whole kernel source tree.
- */
+/* SPDX-License-Identifier: GPL-2.0 */
 
 /** \file list.h Doubly linked list implementation. */
 
+/* Copied from the Linux kernel source tree, version 2.6.13. */
+
 #include <stddef.h> /* offsetof */
 
 /** Get the struct this entry is embedded in. */
diff --git a/lsu.c b/lsu.c
index 4ce4fea8..34613aac 100644
--- a/lsu.c
+++ b/lsu.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 2018 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
+/* SPDX-License-Identifier: GPL-2.0 */
 
 /** \file lsu.c Utilities related to the lopsub library. */
 
diff --git a/lsu.h b/lsu.h
index 6141dfca..1c2ba1cd 100644
--- a/lsu.h
+++ b/lsu.h
@@ -1,4 +1,4 @@
-/* Copyright (C) 2018 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
+/* SPDX-License-Identifier: GPL-2.0 */
 
 /** \file lsu.h Lopsub Utilities, enums and public functions. */
 int lsu_com_help(bool long_help, const struct lls_parse_result *lpr,
diff --git a/mix.h b/mix.h
index 39626d98..697fd993 100644
--- a/mix.h
+++ b/mix.h
@@ -1,4 +1,4 @@
-/* Copyright (C) 2012 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
+/* SPDX-License-Identifier: GPL-2.0 */
 
 /** \file mix.h Mixer API for para_mixer. */
 
diff --git a/mixer.c b/mixer.c
index a607e78d..f5fd92f4 100644
--- a/mixer.c
+++ b/mixer.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 1998 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
+/* SPDX-License-Identifier: GPL-2.0 */
 
 /** \file mixer.c A volume fader and alarm clock.
  *
diff --git a/mood.c b/mood.c
index 2d1e5595..20a5b907 100644
--- a/mood.c
+++ b/mood.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 2007 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
+/* SPDX-License-Identifier: GPL-2.0 */
 
 /** \file mood.c Paraslash's mood handling functions. */
 
diff --git a/mp.c b/mp.c
index 4b86d7c2..62cac28e 100644
--- a/mp.c
+++ b/mp.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 2017 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
+/* SPDX-License-Identifier: GPL-2.0 */
 
 /**
  * \file mp.c Mood parser helper functions.
diff --git a/mp.h b/mp.h
index 891bfb05..c5769246 100644
--- a/mp.h
+++ b/mp.h
@@ -1,4 +1,4 @@
-/* Copyright (C) 2017 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
+/* SPDX-License-Identifier: GPL-2.0 */
 
 /**
  * \file mp.h Internal mood parser API (backend).
diff --git a/mp3_afh.c b/mp3_afh.c
index e0cd6893..ecfced83 100644
--- a/mp3_afh.c
+++ b/mp3_afh.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 2003 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
+/* SPDX-License-Identifier: GPL-2.0 */
 
 /** \file mp3_afh.c para_server's mp3 audio format handler */
 
diff --git a/mp3dec_filter.c b/mp3dec_filter.c
index 7a262d57..2ec5fad5 100644
--- a/mp3dec_filter.c
+++ b/mp3dec_filter.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 2005 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
+/* SPDX-License-Identifier: GPL-2.0 */
 
 /** \file mp3dec_filter.c Paraslash's mp3 decoder. */
 
diff --git a/net.c b/net.c
index 09ee2929..3216e6b9 100644
--- a/net.c
+++ b/net.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 2005 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
+/* SPDX-License-Identifier: GPL-2.0 */
 
 /** \file net.c Networking-related helper functions. */
 
diff --git a/net.h b/net.h
index dd462de6..c8ef6440 100644
--- a/net.h
+++ b/net.h
@@ -1,4 +1,4 @@
-/* Copyright (C) 2006 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
+/* SPDX-License-Identifier: GPL-2.0 */
 /** \file net.h exported symbols from net.c */
 
 /** The maximum length of the host component in an URL. */
diff --git a/ogg_afh.c b/ogg_afh.c
index 1552e643..7679d410 100644
--- a/ogg_afh.c
+++ b/ogg_afh.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 2004 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
+/* SPDX-License-Identifier: GPL-2.0 */
 
 /** \file ogg_afh.c Audio format handler for ogg/vorbis files. */
 
diff --git a/ogg_afh_common.c b/ogg_afh_common.c
index 8e863aa3..7162c341 100644
--- a/ogg_afh_common.c
+++ b/ogg_afh_common.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 2004 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
+/* SPDX-License-Identifier: GPL-2.0 */
 
 /** \file ogg_afh_common.c Functions common to all ogg/ codecs. */
 
diff --git a/ogg_afh_common.h b/ogg_afh_common.h
index 03bf88b5..82a65c34 100644
--- a/ogg_afh_common.h
+++ b/ogg_afh_common.h
@@ -1,4 +1,4 @@
-/* Copyright (C) 2010 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
+/* SPDX-License-Identifier: GPL-2.0 */
 
 /**
  * \file ogg_afh_common.h Structures and prototypes common to audio format
diff --git a/oggdec_filter.c b/oggdec_filter.c
index 0173268f..29e9d190 100644
--- a/oggdec_filter.c
+++ b/oggdec_filter.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 2005 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
+/* SPDX-License-Identifier: GPL-2.0 */
 
 /** \file oggdec_filter.c Paraslash's ogg vorbis decoder. */
 
diff --git a/openssl.c b/openssl.c
index 2c3b7993..b83ee087 100644
--- a/openssl.c
+++ b/openssl.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 2005 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
+/* SPDX-License-Identifier: GPL-2.0 */
 
 /** \file openssl.c Openssl-based encryption/decryption routines. */
 
diff --git a/opus_afh.c b/opus_afh.c
index 5ae07f1f..4c25f470 100644
--- a/opus_afh.c
+++ b/opus_afh.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 2012 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
+/* SPDX-License-Identifier: GPL-2.0 */
 
 /** \file opus_afh.c Audio format handler for ogg/opus files. */
 
diff --git a/opus_common.c b/opus_common.c
index f4e18df9..8827ed8b 100644
--- a/opus_common.c
+++ b/opus_common.c
@@ -1,3 +1,5 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+
 /* Copyright (C)2012 Xiph.Org Foundation
  *
  * Redistribution and use in source and binary forms, with or without
diff --git a/opus_common.h b/opus_common.h
index f8cf459c..0df10b83 100644
--- a/opus_common.h
+++ b/opus_common.h
@@ -1,4 +1,4 @@
-/* Copyright (C) 2013 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
+/* SPDX-License-Identifier: GPL-2.0 */
 
 /**
  * \file opus_common.h
diff --git a/opusdec_filter.c b/opusdec_filter.c
index 8e532301..0453073f 100644
--- a/opusdec_filter.c
+++ b/opusdec_filter.c
@@ -1,10 +1,9 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+
 /*
  * Copyright (c) 2002-2007 Jean-Marc Valin
  * Copyright (c) 2008 CSIRO
  * Copyright (c) 2007-2012 Xiph.Org Foundation
- * Copyright (C) 2012 Andre Noll <maan@tuebingen.mpg.de>
- *
- * Licensed under the GPL v2, see file COPYING.
  */
 
 /** \file opusdec_filter.c The ogg/opus decoder. */
diff --git a/oss_mix.c b/oss_mix.c
index 25147061..c8417a4d 100644
--- a/oss_mix.c
+++ b/oss_mix.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 1998 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
+/* SPDX-License-Identifier: GPL-2.0 */
 
 /** \file oss_mix.c The OSS mixer plugin. */
 
diff --git a/oss_write.c b/oss_write.c
index 1f1c6ac5..4f6d548c 100644
--- a/oss_write.c
+++ b/oss_write.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 2009 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
+/* SPDX-License-Identifier: GPL-2.0 */
 
 /** \file oss_write.c Paraslash's oss output plugin. */
 
diff --git a/para.h b/para.h
index 80fdabc1..228a2c0b 100644
--- a/para.h
+++ b/para.h
@@ -1,4 +1,4 @@
-/* Copyright (C) 1997 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
+/* SPDX-License-Identifier: GPL-2.0 */
 
 /** \file para.h global paraslash definitions */
 
diff --git a/play.c b/play.c
index dcda4456..2cc87845 100644
--- a/play.c
+++ b/play.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 2012 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
+/* SPDX-License-Identifier: GPL-2.0 */
 
 /** \file play.c Standalone command line player.
  *
diff --git a/playlist.c b/playlist.c
index 46e98aef..9ae3028b 100644
--- a/playlist.c
+++ b/playlist.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 2007 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
+/* SPDX-License-Identifier: GPL-2.0 */
 
 #include <osl.h>
 #include <lopsub.h>
diff --git a/portable_io.h b/portable_io.h
index fdd4165d..f1eeb7c7 100644
--- a/portable_io.h
+++ b/portable_io.h
@@ -1,4 +1,4 @@
-/* Copyright (C) 2007 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
+/* SPDX-License-Identifier: GPL-2.0 */
 
 /** \file portable_io.h Inline functions for binary IO. */
 
diff --git a/prebuffer_filter.c b/prebuffer_filter.c
index eafe45a0..c8c44c3c 100644
--- a/prebuffer_filter.c
+++ b/prebuffer_filter.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 2009 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
+/* SPDX-License-Identifier: GPL-2.0 */
 
 /** \file prebuffer_filter.c Paraslash's prebuffering filter. */
 
diff --git a/recv.c b/recv.c
index d0cc91bb..31908bf3 100644
--- a/recv.c
+++ b/recv.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 2005 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
+/* SPDX-License-Identifier: GPL-2.0 */
 
 /** \file recv.c the stand-alone audio stream receiver
  *
diff --git a/recv.h b/recv.h
index 8330bd95..278deb1b 100644
--- a/recv.h
+++ b/recv.h
@@ -1,4 +1,4 @@
-/* Copyright (C) 2005 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
+/* SPDX-License-Identifier: GPL-2.0 */
 
 /** \file recv.h Receiver API
  *
diff --git a/recv_common.c b/recv_common.c
index 9ba7764f..021595a1 100644
--- a/recv_common.c
+++ b/recv_common.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 2006 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
+/* SPDX-License-Identifier: GPL-2.0 */
 
 /** \file recv_common.c common functions of para_recv and para_audiod */
 
diff --git a/ringbuffer.c b/ringbuffer.c
index d737d899..b5b81eb4 100644
--- a/ringbuffer.c
+++ b/ringbuffer.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 2006 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
+/* SPDX-License-Identifier: GPL-2.0 */
 
 /** \file ringbuffer.c Simple ringbuffer implementation */
 
diff --git a/ringbuffer.h b/ringbuffer.h
index 7a5635ca..30e96c76 100644
--- a/ringbuffer.h
+++ b/ringbuffer.h
@@ -1,4 +1,4 @@
-/* Copyright (C) 2006 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
+/* SPDX-License-Identifier: GPL-2.0 */
 
 /** \file ringbuffer.h Exported symbols from ringbuffer.c. */
 
diff --git a/sched.c b/sched.c
index f958a5cd..e4b58b21 100644
--- a/sched.c
+++ b/sched.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 2006 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
+/* SPDX-License-Identifier: GPL-2.0 */
 
 /** \file sched.c Paraslash's scheduling functions. */
 
diff --git a/sched.h b/sched.h
index 4faa431c..e207b4aa 100644
--- a/sched.h
+++ b/sched.h
@@ -1,4 +1,4 @@
-/* Copyright (C) 2006 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
+/* SPDX-License-Identifier: GPL-2.0 */
 
 /** \file sched.h The paraslash scheduler
  *
diff --git a/score.c b/score.c
index 53eb6261..7591d538 100644
--- a/score.c
+++ b/score.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 2007 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
+/* SPDX-License-Identifier: GPL-2.0 */
 
 /** \file score.c Scoring functions to determine the audio file streaming order. */
 #include <osl.h>
diff --git a/send.h b/send.h
index eebffd47..1c8a657c 100644
--- a/send.h
+++ b/send.h
@@ -1,4 +1,4 @@
-/* Copyright (C) 2005 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
+/* SPDX-License-Identifier: GPL-2.0 */
 
 /** \file send.h Sender-related defines and structures.
  *
diff --git a/server.c b/server.c
index f3207b40..94a60b16 100644
--- a/server.c
+++ b/server.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 1997 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
+/* SPDX-License-Identifier: GPL-2.0 */
 
 /** \file server.c Paraslash's main server.
  *
diff --git a/server.h b/server.h
index f89ecaff..009a5f3f 100644
--- a/server.h
+++ b/server.h
@@ -1,4 +1,4 @@
-/* Copyright (C) 1997 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
+/* SPDX-License-Identifier: GPL-2.0 */
 
 /** \file server.h Common server data structures. */
 
diff --git a/sideband.c b/sideband.c
index 4a6ea5bf..6757312c 100644
--- a/sideband.c
+++ b/sideband.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 2012 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
+/* SPDX-License-Identifier: GPL-2.0 */
 
 /** \file sideband.c Implementation of the sideband API. */
 
diff --git a/sideband.h b/sideband.h
index 6b69ebde..51cc6f11 100644
--- a/sideband.h
+++ b/sideband.h
@@ -1,4 +1,4 @@
-/* Copyright (C) 2012 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
+/* SPDX-License-Identifier: GPL-2.0 */
 
 /** \file sideband.h exported symbols from sideband.c */
 
diff --git a/signal.c b/signal.c
index 7cf4bb9f..533a2c66 100644
--- a/signal.c
+++ b/signal.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 2004 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
+/* SPDX-License-Identifier: GPL-2.0 */
 /** \file signal.c Signal handling functions. */
 
 #include <signal.h>
diff --git a/signal.h b/signal.h
index d9e98e78..b4b85cd0 100644
--- a/signal.h
+++ b/signal.h
@@ -1,4 +1,4 @@
-/* Copyright (C) 2007 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
+/* SPDX-License-Identifier: GPL-2.0 */
 
 /** \file signal.h exported symbols from signal.c */
 
diff --git a/spx.h b/spx.h
index 4f46f03b..80015178 100644
--- a/spx.h
+++ b/spx.h
@@ -1,4 +1,4 @@
-/* Copyright (C) 2010 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
+/* SPDX-License-Identifier: GPL-2.0 */
 
 /**
  *  \file spx.h Structures and prototypes common to the speex audio format
diff --git a/spx_afh.c b/spx_afh.c
index fd7a788a..b97d083f 100644
--- a/spx_afh.c
+++ b/spx_afh.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 2010 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
+/* SPDX-License-Identifier: GPL-2.0 */
 
 /* This file is based on speexdec.c, by Jean-Marc Valin, see below. */
 
diff --git a/spx_common.c b/spx_common.c
index e7ef1e79..b6ce91b8 100644
--- a/spx_common.c
+++ b/spx_common.c
@@ -1,9 +1,4 @@
-/*
- * Copyright (C) 2002-2006 Jean-Marc Valin
- * Copyright (C) 2010 Andre Noll <maan@tuebingen.mpg.de>
- *
- * Licensed under the GPL v2, see file COPYING.
- */
+/* SPDX-License-Identifier: GPL-2.0 */
 
 /**
  * \file spx_common.c Functions used by the speex decoder and the speex audio
diff --git a/spxdec_filter.c b/spxdec_filter.c
index df0b4cac..dd2afd11 100644
--- a/spxdec_filter.c
+++ b/spxdec_filter.c
@@ -1,9 +1,4 @@
-/*
- * Copyright (C) 2002-2006 Jean-Marc Valin
- * Copyright (C) 2010 Andre Noll <maan@tuebingen.mpg.de>
- *
- * Licensed under the GPL v2, see file COPYING.
- */
+/* SPDX-License-Identifier: GPL-2.0 */
 
 /** \file spxdec_filter.c Paraslash's ogg/speex decoder. */
 
diff --git a/stat.c b/stat.c
index 1864ff1b..ff7f75dd 100644
--- a/stat.c
+++ b/stat.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 2005 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
+/* SPDX-License-Identifier: GPL-2.0 */
 
 /**
  *  \file stat.c Functions used for sending/receiving the status of para_server
diff --git a/stdin.c b/stdin.c
index 7f711797..5c8f60ca 100644
--- a/stdin.c
+++ b/stdin.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 2006 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
+/* SPDX-License-Identifier: GPL-2.0 */
 
 /** \file stdin.c Functions that deal with reading from stdin. */
 
diff --git a/stdin.h b/stdin.h
index 67217db6..e72de69f 100644
--- a/stdin.h
+++ b/stdin.h
@@ -1,4 +1,4 @@
-/* Copyright (C) 2006 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
+/* SPDX-License-Identifier: GPL-2.0 */
 
 /** \file stdin.h The stdin task and buffer tree node. */
 
diff --git a/stdout.c b/stdout.c
index daaecb0c..11990c81 100644
--- a/stdout.c
+++ b/stdout.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 2006 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
+/* SPDX-License-Identifier: GPL-2.0 */
 
 /** \file stdout.c Functions that deal with writing to stdout. */
 
diff --git a/stdout.h b/stdout.h
index 7c9cb3fc..6f100fc3 100644
--- a/stdout.h
+++ b/stdout.h
@@ -1,4 +1,4 @@
-/* Copyright (C) 2006 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
+/* SPDX-License-Identifier: GPL-2.0 */
 
 /** \file stdout.h Writing to stdout via buffer trees. */
 
diff --git a/string.c b/string.c
index 0dbe3425..0d7223c0 100644
--- a/string.c
+++ b/string.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 2004 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
+/* SPDX-License-Identifier: GPL-2.0 */
 
 /** \file string.c Memory allocation and string handling functions. */
 
diff --git a/string.h b/string.h
index ec619fa8..20604a40 100644
--- a/string.h
+++ b/string.h
@@ -1,4 +1,4 @@
-/* Copyright (C) 2006 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
+/* SPDX-License-Identifier: GPL-2.0 */
 
 /** \file string.h exported symbols from string.c */
 
diff --git a/sync_filter.c b/sync_filter.c
index eba67f8e..81b611b0 100644
--- a/sync_filter.c
+++ b/sync_filter.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 2013 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
+/* SPDX-License-Identifier: GPL-2.0 */
 
 /** \file sync_filter.c Playback synchronization filter. */
 
diff --git a/time.c b/time.c
index bb47b31b..1b51ef23 100644
--- a/time.c
+++ b/time.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 2005 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
+/* SPDX-License-Identifier: GPL-2.0 */
 
 #include "para.h"
 /** \file time.c Helper functions for dealing with time values. */
diff --git a/udp_recv.c b/udp_recv.c
index fc0b43eb..71ae4076 100644
--- a/udp_recv.c
+++ b/udp_recv.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 2005 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
+/* SPDX-License-Identifier: GPL-2.0 */
 /** \file udp_recv.c Paraslash's udp receiver */
 
 #include <netinet/in.h>
diff --git a/udp_send.c b/udp_send.c
index 10a4e525..a40f7045 100644
--- a/udp_send.c
+++ b/udp_send.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 2005 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
+/* SPDX-License-Identifier: GPL-2.0 */
 
 /** \file udp_send.c Para_server's udp sender. */
 
diff --git a/vss.c b/vss.c
index d888d409..a60112f8 100644
--- a/vss.c
+++ b/vss.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 1997 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
+/* SPDX-License-Identifier: GPL-2.0 */
 
 /** \file vss.c The virtual streaming system.
  *
diff --git a/vss.h b/vss.h
index 75551a2f..3afd688e 100644
--- a/vss.h
+++ b/vss.h
@@ -1,4 +1,4 @@
-/* Copyright (C) 2005 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
+/* SPDX-License-Identifier: GPL-2.0 */
 
 /** \file vss.h The virtual streaming system API.
  *
diff --git a/wav_filter.c b/wav_filter.c
index 2c2e5fe2..9157c66f 100644
--- a/wav_filter.c
+++ b/wav_filter.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 2005 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
+/* SPDX-License-Identifier: GPL-2.0 */
 
 /** \file wav_filter.c A filter that inserts a wave header. */
 
diff --git a/wma_afh.c b/wma_afh.c
index 725dc205..1d89d79d 100644
--- a/wma_afh.c
+++ b/wma_afh.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 2009 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
+/* SPDX-License-Identifier: GPL-2.0 */
 
 /** \file wma_afh.c The audio format handler for WMA files. */
 
diff --git a/wma_common.c b/wma_common.c
index 0c8c8835..05828549 100644
--- a/wma_common.c
+++ b/wma_common.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 2009 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
+/* SPDX-License-Identifier: GPL-2.0 */
 
 /** \file wma_common.c Functions used by both the WMA afh and decoder. */
 
diff --git a/write.c b/write.c
index a01a3688..22c5cb25 100644
--- a/write.c
+++ b/write.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 2005 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
+/* SPDX-License-Identifier: GPL-2.0 */
 
 /** \file write.c Paraslash's standalone wav/raw player.
  *
diff --git a/write.h b/write.h
index 6521ec0e..9998989a 100644
--- a/write.h
+++ b/write.h
@@ -1,4 +1,4 @@
-/* Copyright (C) 2006 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
+/* SPDX-License-Identifier: GPL-2.0 */
 
 /** \file write.h Writer API
  *
diff --git a/write_common.c b/write_common.c
index acf693a3..22e35662 100644
--- a/write_common.c
+++ b/write_common.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 2006 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
+/* SPDX-License-Identifier: GPL-2.0 */
 
 /** \file write_common.c common functions of para_audiod and para_write */
 
diff --git a/yy/mp.lex b/yy/mp.lex
index 27e968bf..5a3ce4f9 100644
--- a/yy/mp.lex
+++ b/yy/mp.lex
@@ -1,4 +1,4 @@
-/* Copyright (C) 2017 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
+/* SPDX-License-Identifier: GPL-2.0 */
 
  /*
   * Since we do not supply yywrap(), we use noyywrap to instruct the scanner to
diff --git a/yy/mp.y b/yy/mp.y
index f2f0756d..1892ebbc 100644
--- a/yy/mp.y
+++ b/yy/mp.y
@@ -1,4 +1,4 @@
-/* Copyright (C) 2017 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
+/* SPDX-License-Identifier: GPL-2.0 */
 
 /*
  * Provide more verbose and specific error messages instead of just "syntax