Apply script to each file on command line.

For this to work, the script must be seekable. And to avoid infinite
loops, if the script modifies the input file list, it is only applied
to the first file on the command line.

src/buf.c

@@ -1,6 +1,6 @@
 /* buf.c: Buffer routines for the ed line editor.
  *
- *  Copyright © 1993-2022 Andrew L. Moore, SlewSys Research
+ *  Copyright © 1993-2024 Andrew L. Moore, SlewSys Research
  *
  *  SPDX-License-Identifier:  BSD-2-Clause OR GPL-2.0-or-later OR MIT
  */
@@ -193,8 +193,8 @@ init_ed_command (int init_glob, ed_buffer_t *ed)
   /* File info */
 #ifdef WANT_FILE_LOCK
 
-  /* GNU/Linux double-frees on fclose() here... */
-#if __linux__
+  /* XXX: GNU/Linux double-frees on fclose().  */
+#ifndef __linux__
   if (ed->file->handle)
 
     /* Assert: No writes since fopen(3). */

src/io.c

@@ -1,6 +1,6 @@
 /* io.c: I/O routines for the ed line editor.
  *
- *  Copyright © 1993-2022 Andrew L. Moore, SlewSys Research
+ *  Copyright © 1993-2024 Andrew L. Moore, SlewSys Research
  *
  *  SPDX-License-Identifier:  BSD-2-Clause OR GPL-2.0-or-later OR MIT
  */
@@ -615,7 +615,8 @@ write_file (const char *fn, int is_default, off_t from, off_t to,
    * File-locking requires file write access, so this case should not
    * be reached.
    */
-  else if (file_already_open && fclose (ed->file->handle) < 0)
+  else if (file_already_open
+           && (fclose (ed->file->handle) < 0 || !(ed->file->handle = NULL)))
     {
       fprintf (stderr, "%s: %s\n", ed->file->name, strerror (errno));
       ed->exec->err = _("File close error");

src/main.c

@@ -1,6 +1,6 @@
 /* main.c: Entry point for the ed line editor.
  *
- *  Copyright © 1993-2023 Andrew L. Moore, SlewSys Research
+ *  Copyright © 1993-2024 Andrew L. Moore, SlewSys Research
  *
  *  SPDX-License-Identifier:  BSD-2-Clause OR GPL-2.0-or-later OR MIT
  */
@@ -410,6 +410,13 @@ main (int argc, char **argv)
             goto error;
 #endif
 
+          /* Command-line files still available and stdin seekable... */
+          if (ed->file->list->gl_offs && ed->file->list->gl_pathc > 1
+              && FSEEK(stdin, 0L, SEEK_SET) != -1)
+            {
+              status = EOF_NEXT;
+              goto next;
+            }
           quit (ed->exec->status, ed);
         case EMOD:
           ed->exec->err = _("WARNING: Buffer modified since last write");